ALL

Although the only pediatric indication for chimeric antigen receptor T-cell therapy currently approved by the Food and Drug Administration is B-lineage acute lymphoblastic leukemia (ALL) that is refractory to at least two frontline induction attempts or is in second or later relapse, clinical trials of CAR-T therapy for pediatric solid tumors are also currently in progress, said Gregory Yanik, MD, from the CS Mott Children’s Hospital at the University of Michigan, Ann Arbor, at the Transplant & Cellular Therapies Meetings.

In his presentation, Dr. Yanik discussed progress in solid tumor studies as well as some issues involving the current use of CAR-T therapy for ALL.

Solid tumor studies

Malignancies such as sarcomas, brain tumors, and neuroblastomas pose unique challenges, “In contrast to hematologic malignancies, the protein we’re targeting may not be present on the cell surface of all the tumor cells. There are lower-expression profiles, and this is a problem. In fact, many people have postulated that with CAR-T for pediatric solid tumors we’ll have to do repeated cycles, almost like we do with chemotherapy,” he said at the meeting held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

There are currently 14 studies of CAR-T for central nervous system tumors in children, targeting either epidermal growth factor receptor (EGFR) in glioblastoma multiforme and high-grade gliomas, HER2 in a variety of CNS tumors, the GD2 antigen on pontine gliomas, and the checkpoint molecular B7H3 in medulloblastomas and pontine gliomas.

“In sarcomas in kids there are currently 12 trials in progress. Most of the targeting epitopes are targeting either HER2 or GD2. Repetitive CAR-T infusions are being used in several of these trials in sarcomas.

For neuroblastomas there are currently 13 studies in progress, nearly all of which target GD2. Some of the trials include combining CAR-T with immune checkpoint inhibitors or C7R, an engineered cytokine driver designed to prevent T-cell exhaustion.

In addition, several trials of tumor pulsed dendritic cell vaccines are underway for treatment of children with Wilms tumor, Dr. Yanik noted.
 

Unresolved procedural questions

It’s still early days in CAR-T therapy, and there are several still unanswered questions regarding optimal therapy for and management of patients undergoing CAR-T procedures, Dr. Yanik said.

For example, the optimal time to collect T cells during apheresis is still unclear, he said. Collecting prior to reinduction therapy raises the risk of transducing leukemic cells, while collecting after reinduction may result in inadequate quantity or quality of cells. Regardless of when cells are collected, apheresis should be performed only when the absolute lymphocyte count is above 500/mcL or the CD3 count is above 150/mcL at the time of apheresis.

In the case tisagenlecleucel (Kymriah), his center typically collects 1x10⁹ CD3 cells regardless of age or weight.

The number of CAR T-cells infused also appears to matter, as responses are improved at CAR-T doses above 1.5x10⁶/kg, while risk for higher-grade cytokine release syndrome (CRS) occurs at higher infusion doses.
 

Blinatumomab or inotuzumab?

Along with CAR-T, two other agents, the bispecific T-cell engager blinatumomab (Blincyto) and the antibody conjugate inotuzumab ozogamicin (Besponsa) are also approved for the treatment of patients with relapsed/refractory B-cell ALL.

Like CAR-T therapy, the primary toxicities associated with blinatumomab are CRS and neurologic adverse events, whereas at inotuzumab is largely associated with hematologic and hepatic toxicities.

The logistics of therapy differ widely, with a 28-day infusion required for blinatumomab, compared with weekly dosing of inotuzumab, and the multiple visits for apheresis and infusion required for CAR-T.

Blinatumomab is approved for both children and adults with relapsed/refractory ALL, but inotuzumab is approved only for adults, and CAR-T with tisagenlecleucel is approved only for children in this indication.
 

CD-19 expression

There is evidence to suggest that CD19 expression prior to CAR-T has an effect on outcomes, Dr. Yanik said.

“Does blinatumomab pre–CAR-T impact outcome? The answer is probably yes,” he said.

He referred to a study by investigators at the Children’s Hospital of Philadelphia showing that, “if you’re giving blinatumomab prior to CAR-T therapy, you’re potentially reducing the cell-surface expression of CD19 on your leukemic blasts, and now while you’re bringing these patients in for CAR-T therapy, you’re getting a much higher population of dim CD19 expressers, and this is associated with a higher relapse rate and lower remission rate.”
 

Predicting relapse

Dr. Yanik referred to a study, currently unpublished, which will show that next-generation sequencing (NGS) is more sensitive than flow cytometry for detection of minimal residual disease (MRD), and that MRD analysis of marrow was more sensitive than analysis of peripheral blood.

“Poor outcomes were seen post CAR-T for patients who were in morphologic remission on day 28 or day 100, but had positive MRD. This especially held true if it was next-gen sequencing MRD-positive at day 100, for which relapse rates were over 95%,” he said.

The absence of B-cells is a surrogate marker for the persistence of CAR-T, and conversely, the recovery of CD19-positive B cells may be a predictor for relapse, especially if the B-cell recovery occurs within the first 6 months following CAR-T infusion.
 

Transplant after CAR-T?

Bone marrow transplant after CAR-T is recommend for patients with high risk of relapse, including those with B-cell recovery within the first 6 months after CAR-T, patients with MRD positivity at days 28 or 100, and patients with mixed lineage leukemia.

“Should we transplant good-risk patients, meaning, if you have NGS-MRD negative patients, is there a role for transplant? You have to look at the risk versus benefit there. These patients may have a cure rate that’s in the 80%-plus range, could we potentially optimize that even more if we consolidate them with an allo[geneic] transplant,” Dr. Yank said.
 

Move CAR-T up front?

A Children’s Oncology Group study is currently examining whether giving CAR-T therapy to patients with MRD of 0.01% or greater following first consolidation could result in lower tumor burden, fewer relapse, and less CRS with CAR-T.

Dr. Yanik reported that he had no conflicts of interest to disclose.

Although the only pediatric indication for chimeric antigen receptor T-cell therapy currently approved by the Food and Drug Administration is B-lineage acute lymphoblastic leukemia (ALL) that is refractory to at least two frontline induction attempts or is in second or later relapse, clinical trials of CAR-T therapy for pediatric solid tumors are also currently in progress, said Gregory Yanik, MD, from the CS Mott Children’s Hospital at the University of Michigan, Ann Arbor, at the Transplant & Cellular Therapies Meetings.

In his presentation, Dr. Yanik discussed progress in solid tumor studies as well as some issues involving the current use of CAR-T therapy for ALL.

Solid tumor studies

Malignancies such as sarcomas, brain tumors, and neuroblastomas pose unique challenges, “In contrast to hematologic malignancies, the protein we’re targeting may not be present on the cell surface of all the tumor cells. There are lower-expression profiles, and this is a problem. In fact, many people have postulated that with CAR-T for pediatric solid tumors we’ll have to do repeated cycles, almost like we do with chemotherapy,” he said at the meeting held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

There are currently 14 studies of CAR-T for central nervous system tumors in children, targeting either epidermal growth factor receptor (EGFR) in glioblastoma multiforme and high-grade gliomas, HER2 in a variety of CNS tumors, the GD2 antigen on pontine gliomas, and the checkpoint molecular B7H3 in medulloblastomas and pontine gliomas.

“In sarcomas in kids there are currently 12 trials in progress. Most of the targeting epitopes are targeting either HER2 or GD2. Repetitive CAR-T infusions are being used in several of these trials in sarcomas.

For neuroblastomas there are currently 13 studies in progress, nearly all of which target GD2. Some of the trials include combining CAR-T with immune checkpoint inhibitors or C7R, an engineered cytokine driver designed to prevent T-cell exhaustion.

In addition, several trials of tumor pulsed dendritic cell vaccines are underway for treatment of children with Wilms tumor, Dr. Yanik noted.
 

Unresolved procedural questions

It’s still early days in CAR-T therapy, and there are several still unanswered questions regarding optimal therapy for and management of patients undergoing CAR-T procedures, Dr. Yanik said.

For example, the optimal time to collect T cells during apheresis is still unclear, he said. Collecting prior to reinduction therapy raises the risk of transducing leukemic cells, while collecting after reinduction may result in inadequate quantity or quality of cells. Regardless of when cells are collected, apheresis should be performed only when the absolute lymphocyte count is above 500/mcL or the CD3 count is above 150/mcL at the time of apheresis.

In the case tisagenlecleucel (Kymriah), his center typically collects 1x10⁹ CD3 cells regardless of age or weight.

The number of CAR T-cells infused also appears to matter, as responses are improved at CAR-T doses above 1.5x10⁶/kg, while risk for higher-grade cytokine release syndrome (CRS) occurs at higher infusion doses.
 

Blinatumomab or inotuzumab?

Along with CAR-T, two other agents, the bispecific T-cell engager blinatumomab (Blincyto) and the antibody conjugate inotuzumab ozogamicin (Besponsa) are also approved for the treatment of patients with relapsed/refractory B-cell ALL.

Like CAR-T therapy, the primary toxicities associated with blinatumomab are CRS and neurologic adverse events, whereas at inotuzumab is largely associated with hematologic and hepatic toxicities.

The logistics of therapy differ widely, with a 28-day infusion required for blinatumomab, compared with weekly dosing of inotuzumab, and the multiple visits for apheresis and infusion required for CAR-T.

Blinatumomab is approved for both children and adults with relapsed/refractory ALL, but inotuzumab is approved only for adults, and CAR-T with tisagenlecleucel is approved only for children in this indication.
 

CD-19 expression

There is evidence to suggest that CD19 expression prior to CAR-T has an effect on outcomes, Dr. Yanik said.

“Does blinatumomab pre–CAR-T impact outcome? The answer is probably yes,” he said.

He referred to a study by investigators at the Children’s Hospital of Philadelphia showing that, “if you’re giving blinatumomab prior to CAR-T therapy, you’re potentially reducing the cell-surface expression of CD19 on your leukemic blasts, and now while you’re bringing these patients in for CAR-T therapy, you’re getting a much higher population of dim CD19 expressers, and this is associated with a higher relapse rate and lower remission rate.”
 

Predicting relapse

Dr. Yanik referred to a study, currently unpublished, which will show that next-generation sequencing (NGS) is more sensitive than flow cytometry for detection of minimal residual disease (MRD), and that MRD analysis of marrow was more sensitive than analysis of peripheral blood.

“Poor outcomes were seen post CAR-T for patients who were in morphologic remission on day 28 or day 100, but had positive MRD. This especially held true if it was next-gen sequencing MRD-positive at day 100, for which relapse rates were over 95%,” he said.

The absence of B-cells is a surrogate marker for the persistence of CAR-T, and conversely, the recovery of CD19-positive B cells may be a predictor for relapse, especially if the B-cell recovery occurs within the first 6 months following CAR-T infusion.
 

Transplant after CAR-T?

Bone marrow transplant after CAR-T is recommend for patients with high risk of relapse, including those with B-cell recovery within the first 6 months after CAR-T, patients with MRD positivity at days 28 or 100, and patients with mixed lineage leukemia.

“Should we transplant good-risk patients, meaning, if you have NGS-MRD negative patients, is there a role for transplant? You have to look at the risk versus benefit there. These patients may have a cure rate that’s in the 80%-plus range, could we potentially optimize that even more if we consolidate them with an allo[geneic] transplant,” Dr. Yank said.
 

Move CAR-T up front?

A Children’s Oncology Group study is currently examining whether giving CAR-T therapy to patients with MRD of 0.01% or greater following first consolidation could result in lower tumor burden, fewer relapse, and less CRS with CAR-T.

Dr. Yanik reported that he had no conflicts of interest to disclose.

Although the only pediatric indication for chimeric antigen receptor T-cell therapy currently approved by the Food and Drug Administration is B-lineage acute lymphoblastic leukemia (ALL) that is refractory to at least two frontline induction attempts or is in second or later relapse, clinical trials of CAR-T therapy for pediatric solid tumors are also currently in progress, said Gregory Yanik, MD, from the CS Mott Children’s Hospital at the University of Michigan, Ann Arbor, at the Transplant & Cellular Therapies Meetings.

In his presentation, Dr. Yanik discussed progress in solid tumor studies as well as some issues involving the current use of CAR-T therapy for ALL.

Solid tumor studies

Malignancies such as sarcomas, brain tumors, and neuroblastomas pose unique challenges, “In contrast to hematologic malignancies, the protein we’re targeting may not be present on the cell surface of all the tumor cells. There are lower-expression profiles, and this is a problem. In fact, many people have postulated that with CAR-T for pediatric solid tumors we’ll have to do repeated cycles, almost like we do with chemotherapy,” he said at the meeting held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

There are currently 14 studies of CAR-T for central nervous system tumors in children, targeting either epidermal growth factor receptor (EGFR) in glioblastoma multiforme and high-grade gliomas, HER2 in a variety of CNS tumors, the GD2 antigen on pontine gliomas, and the checkpoint molecular B7H3 in medulloblastomas and pontine gliomas.

“In sarcomas in kids there are currently 12 trials in progress. Most of the targeting epitopes are targeting either HER2 or GD2. Repetitive CAR-T infusions are being used in several of these trials in sarcomas.

For neuroblastomas there are currently 13 studies in progress, nearly all of which target GD2. Some of the trials include combining CAR-T with immune checkpoint inhibitors or C7R, an engineered cytokine driver designed to prevent T-cell exhaustion.

In addition, several trials of tumor pulsed dendritic cell vaccines are underway for treatment of children with Wilms tumor, Dr. Yanik noted.
 

Unresolved procedural questions

It’s still early days in CAR-T therapy, and there are several still unanswered questions regarding optimal therapy for and management of patients undergoing CAR-T procedures, Dr. Yanik said.

For example, the optimal time to collect T cells during apheresis is still unclear, he said. Collecting prior to reinduction therapy raises the risk of transducing leukemic cells, while collecting after reinduction may result in inadequate quantity or quality of cells. Regardless of when cells are collected, apheresis should be performed only when the absolute lymphocyte count is above 500/mcL or the CD3 count is above 150/mcL at the time of apheresis.

In the case tisagenlecleucel (Kymriah), his center typically collects 1x10⁹ CD3 cells regardless of age or weight.

The number of CAR T-cells infused also appears to matter, as responses are improved at CAR-T doses above 1.5x10⁶/kg, while risk for higher-grade cytokine release syndrome (CRS) occurs at higher infusion doses.
 

Blinatumomab or inotuzumab?

Along with CAR-T, two other agents, the bispecific T-cell engager blinatumomab (Blincyto) and the antibody conjugate inotuzumab ozogamicin (Besponsa) are also approved for the treatment of patients with relapsed/refractory B-cell ALL.

Like CAR-T therapy, the primary toxicities associated with blinatumomab are CRS and neurologic adverse events, whereas at inotuzumab is largely associated with hematologic and hepatic toxicities.

The logistics of therapy differ widely, with a 28-day infusion required for blinatumomab, compared with weekly dosing of inotuzumab, and the multiple visits for apheresis and infusion required for CAR-T.

Blinatumomab is approved for both children and adults with relapsed/refractory ALL, but inotuzumab is approved only for adults, and CAR-T with tisagenlecleucel is approved only for children in this indication.
 

CD-19 expression

There is evidence to suggest that CD19 expression prior to CAR-T has an effect on outcomes, Dr. Yanik said.

“Does blinatumomab pre–CAR-T impact outcome? The answer is probably yes,” he said.

He referred to a study by investigators at the Children’s Hospital of Philadelphia showing that, “if you’re giving blinatumomab prior to CAR-T therapy, you’re potentially reducing the cell-surface expression of CD19 on your leukemic blasts, and now while you’re bringing these patients in for CAR-T therapy, you’re getting a much higher population of dim CD19 expressers, and this is associated with a higher relapse rate and lower remission rate.”
 

Predicting relapse

Dr. Yanik referred to a study, currently unpublished, which will show that next-generation sequencing (NGS) is more sensitive than flow cytometry for detection of minimal residual disease (MRD), and that MRD analysis of marrow was more sensitive than analysis of peripheral blood.

“Poor outcomes were seen post CAR-T for patients who were in morphologic remission on day 28 or day 100, but had positive MRD. This especially held true if it was next-gen sequencing MRD-positive at day 100, for which relapse rates were over 95%,” he said.

The absence of B-cells is a surrogate marker for the persistence of CAR-T, and conversely, the recovery of CD19-positive B cells may be a predictor for relapse, especially if the B-cell recovery occurs within the first 6 months following CAR-T infusion.
 

Transplant after CAR-T?

Bone marrow transplant after CAR-T is recommend for patients with high risk of relapse, including those with B-cell recovery within the first 6 months after CAR-T, patients with MRD positivity at days 28 or 100, and patients with mixed lineage leukemia.

“Should we transplant good-risk patients, meaning, if you have NGS-MRD negative patients, is there a role for transplant? You have to look at the risk versus benefit there. These patients may have a cure rate that’s in the 80%-plus range, could we potentially optimize that even more if we consolidate them with an allo[geneic] transplant,” Dr. Yank said.
 

Move CAR-T up front?

A Children’s Oncology Group study is currently examining whether giving CAR-T therapy to patients with MRD of 0.01% or greater following first consolidation could result in lower tumor burden, fewer relapse, and less CRS with CAR-T.

Dr. Yanik reported that he had no conflicts of interest to disclose.

A novel T-cell engineered product, Orca-T (Orca Bio), was associated with lower incidence of both acute and chronic graft-versus-host disease (GVHD) and more than double the rate of GVHD-free and relapse-free survival, compared with the current standard of care for patients undergoing hematopoietic stem cell transplants (HSCT), investigators said.

In both a multicenter phase 1 trial (NCT04013685) and single-center phase 1/2 trial (NCT01660607) with a total of 50 patients, those who received Orca-T with single-agent GVHD prophylaxis had a 1-year GVHD-free and relapse-free survival rate of 75%, compared with 31% for patients who received standard of care with two-agent prophylaxis, reported Everett H. Meyer, MD, PhD, from the Stanford (Calif.) University.

“Orca-T has good evidence for reduced acute graft-versus-host disease, reduced chromic graft-versus-host disease, and a low nonrelapse mortality,” he said at the Transplant & Cellular Therapies Meetings.

The product can be quickly manufactured and delivered to treatment centers across the continental United States, with “vein-to-vein” time of less than 72 hours, he said at the meeting held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

Orca-T consists of highly purified, donor-derived T-regulatory (Treg) cells that are sorted and delivered on day 0 with hematopoietic stem cells, without immunosuppressants, followed 2 days later with infusion of a matching dose of conventional T cells.

“The Treg cells are allowed to expand to create the right microenvironment for the [conventional T cells],” he explained.

In preclinical studies, donor-derived, high-purity Tregs delivered prior to adoptive transfer of conventional T cells prevented GVHD while maintaining graft-versus-tumor immunity, he said.
 

Two T-cell infusions

He reported updated results from current studies on a total of 50 adults, with a cohort of 144 patients treated concurrently with standard of care as controls.

The Orca-T–treated patients had a median age of 47 and 52% were male. Indications for transplant included acute myeloid and acute lymphoblastic leukemia, chronic myeloid leukemia, B-cell lymphoma, myelodysplastic syndrome/myelofibrosis, and other unspecified indications.

In both the Orca-T and control cohorts, patients underwent myeloablative conditioning from 10 to 2 days prior to stem cell infusion.

As noted patients in the experimental arm received infusion of hematopoietic stem/progenitor cells and Tregs, followed 2 days later by conventional T-cell infusion, and, on the day after that, tacrolimus at a target dose of 4.6 ng/mL. The conventional T cells were reserved from donor apheresis and were otherwise unmanipulated prior to infusion into the recipient, Dr. Meyer noted.

Patients in the standard-of-care arm received tacrolimus on the day before standard infusion of the apheresis product, followed by methotrexate prophylaxis on days 1, 3, 6 and 11.

Time to neutrophil engraftment, platelet engraftment, and from day 0 to hospital discharge were all significantly shorter in the Orca-T group, at 12 versus 14 days (P < .0001), 11 vs. 17 days (P < .0001), and 15 vs. 17 days (P = .01) respectively.

At 100 days of follow-up, the rate of grade 2 or greater acute GVHD was 30% among standard-of-care patients versus 10% among Orca-T–treated patients. At 1-year follow-up, respective rates of chronic GVHD were 46% vs. 3%.
 

Safety

“In general, the protocol is extremely well tolerated by our patients. We’ve seen no exceptional infectious disease complications, and we’ve seen no other major complications,” Dr. Meyer said.

Cytomegalovirus prophylaxis was used variably, depending on the center and on the attending physician. Epstein-Barr virus reactivation occurred in eight patients, with one requiring therapy, but there was no biopsy or radiographic evidence of posttransplant lymphoproliferative disorder.

In all, 18% of patients had serious adverse events during the reporting period, all of which resolved. There were no treatment-related deaths in the Orca-T arm, compared with 11% of controls.
 

Engraftment differences explored

In the question-and-answer session following the presentation, Christopher J. Gamper, MD, PhD, from the Johns Hopkins Hospital in Baltimore, told Dr. Meyer that “your outcomes from Orca-T look excellent,” and asked about the cost differential, compared with similar, unmanipulated transplants performed with standard GVHD prophylaxis.

“Is this recovered by lower costs for treatment of GVHD?” he asked.

“I have not done an economic cost analysis of course, and I think others may be looking into this,” Dr. Meyer replied. “Graft engineering can be expensive, although it’s an engineering proposition and one could imagine that the costs will go down substantially over time.”

Session moderator Alan Hanash, MD, PhD, from Memorial Sloan Kettering Cancer Center in New York, commented on the differences in engraftment between the experimental controls arms, and asked Dr. Meyer: “Do you think this is due to the difference in prophylaxis? Absence of methotrexate? Do you think that it could be a direct impact of regulatory T cells on hematopoietic engraftment?”

“Certainly not having methotrexate is beneficial for engraftment, and may account for the differences we see, Dr. Meyer said. “However, it is possible that Tregs could be playing a facilitative role. There certainly is good preclinical literature that Tregs, particularly in the bone marrow space, can facilitate bone marrow engraftment.”

The Orca-T trials are sponsored by Orca Bio and Stanford, with support from the National Institutes of Health. Dr. Meyer receives research support from Orca and is a scientific adviser to GigaGen, Triursus, Incyte, and Indee Labs. Dr. Hanash and Dr. Gamper had no relevant disclosures.

A novel T-cell engineered product, Orca-T (Orca Bio), was associated with lower incidence of both acute and chronic graft-versus-host disease (GVHD) and more than double the rate of GVHD-free and relapse-free survival, compared with the current standard of care for patients undergoing hematopoietic stem cell transplants (HSCT), investigators said.

In both a multicenter phase 1 trial (NCT04013685) and single-center phase 1/2 trial (NCT01660607) with a total of 50 patients, those who received Orca-T with single-agent GVHD prophylaxis had a 1-year GVHD-free and relapse-free survival rate of 75%, compared with 31% for patients who received standard of care with two-agent prophylaxis, reported Everett H. Meyer, MD, PhD, from the Stanford (Calif.) University.

“Orca-T has good evidence for reduced acute graft-versus-host disease, reduced chromic graft-versus-host disease, and a low nonrelapse mortality,” he said at the Transplant & Cellular Therapies Meetings.

The product can be quickly manufactured and delivered to treatment centers across the continental United States, with “vein-to-vein” time of less than 72 hours, he said at the meeting held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

Orca-T consists of highly purified, donor-derived T-regulatory (Treg) cells that are sorted and delivered on day 0 with hematopoietic stem cells, without immunosuppressants, followed 2 days later with infusion of a matching dose of conventional T cells.

“The Treg cells are allowed to expand to create the right microenvironment for the [conventional T cells],” he explained.

In preclinical studies, donor-derived, high-purity Tregs delivered prior to adoptive transfer of conventional T cells prevented GVHD while maintaining graft-versus-tumor immunity, he said.
 

Two T-cell infusions

He reported updated results from current studies on a total of 50 adults, with a cohort of 144 patients treated concurrently with standard of care as controls.

The Orca-T–treated patients had a median age of 47 and 52% were male. Indications for transplant included acute myeloid and acute lymphoblastic leukemia, chronic myeloid leukemia, B-cell lymphoma, myelodysplastic syndrome/myelofibrosis, and other unspecified indications.

In both the Orca-T and control cohorts, patients underwent myeloablative conditioning from 10 to 2 days prior to stem cell infusion.

As noted patients in the experimental arm received infusion of hematopoietic stem/progenitor cells and Tregs, followed 2 days later by conventional T-cell infusion, and, on the day after that, tacrolimus at a target dose of 4.6 ng/mL. The conventional T cells were reserved from donor apheresis and were otherwise unmanipulated prior to infusion into the recipient, Dr. Meyer noted.

Patients in the standard-of-care arm received tacrolimus on the day before standard infusion of the apheresis product, followed by methotrexate prophylaxis on days 1, 3, 6 and 11.

Time to neutrophil engraftment, platelet engraftment, and from day 0 to hospital discharge were all significantly shorter in the Orca-T group, at 12 versus 14 days (P < .0001), 11 vs. 17 days (P < .0001), and 15 vs. 17 days (P = .01) respectively.

At 100 days of follow-up, the rate of grade 2 or greater acute GVHD was 30% among standard-of-care patients versus 10% among Orca-T–treated patients. At 1-year follow-up, respective rates of chronic GVHD were 46% vs. 3%.
 

Safety

“In general, the protocol is extremely well tolerated by our patients. We’ve seen no exceptional infectious disease complications, and we’ve seen no other major complications,” Dr. Meyer said.

Cytomegalovirus prophylaxis was used variably, depending on the center and on the attending physician. Epstein-Barr virus reactivation occurred in eight patients, with one requiring therapy, but there was no biopsy or radiographic evidence of posttransplant lymphoproliferative disorder.

In all, 18% of patients had serious adverse events during the reporting period, all of which resolved. There were no treatment-related deaths in the Orca-T arm, compared with 11% of controls.
 

Engraftment differences explored

In the question-and-answer session following the presentation, Christopher J. Gamper, MD, PhD, from the Johns Hopkins Hospital in Baltimore, told Dr. Meyer that “your outcomes from Orca-T look excellent,” and asked about the cost differential, compared with similar, unmanipulated transplants performed with standard GVHD prophylaxis.

“Is this recovered by lower costs for treatment of GVHD?” he asked.

“I have not done an economic cost analysis of course, and I think others may be looking into this,” Dr. Meyer replied. “Graft engineering can be expensive, although it’s an engineering proposition and one could imagine that the costs will go down substantially over time.”

Session moderator Alan Hanash, MD, PhD, from Memorial Sloan Kettering Cancer Center in New York, commented on the differences in engraftment between the experimental controls arms, and asked Dr. Meyer: “Do you think this is due to the difference in prophylaxis? Absence of methotrexate? Do you think that it could be a direct impact of regulatory T cells on hematopoietic engraftment?”

“Certainly not having methotrexate is beneficial for engraftment, and may account for the differences we see, Dr. Meyer said. “However, it is possible that Tregs could be playing a facilitative role. There certainly is good preclinical literature that Tregs, particularly in the bone marrow space, can facilitate bone marrow engraftment.”

The Orca-T trials are sponsored by Orca Bio and Stanford, with support from the National Institutes of Health. Dr. Meyer receives research support from Orca and is a scientific adviser to GigaGen, Triursus, Incyte, and Indee Labs. Dr. Hanash and Dr. Gamper had no relevant disclosures.

A novel T-cell engineered product, Orca-T (Orca Bio), was associated with lower incidence of both acute and chronic graft-versus-host disease (GVHD) and more than double the rate of GVHD-free and relapse-free survival, compared with the current standard of care for patients undergoing hematopoietic stem cell transplants (HSCT), investigators said.

In both a multicenter phase 1 trial (NCT04013685) and single-center phase 1/2 trial (NCT01660607) with a total of 50 patients, those who received Orca-T with single-agent GVHD prophylaxis had a 1-year GVHD-free and relapse-free survival rate of 75%, compared with 31% for patients who received standard of care with two-agent prophylaxis, reported Everett H. Meyer, MD, PhD, from the Stanford (Calif.) University.

“Orca-T has good evidence for reduced acute graft-versus-host disease, reduced chromic graft-versus-host disease, and a low nonrelapse mortality,” he said at the Transplant & Cellular Therapies Meetings.

The product can be quickly manufactured and delivered to treatment centers across the continental United States, with “vein-to-vein” time of less than 72 hours, he said at the meeting held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

Orca-T consists of highly purified, donor-derived T-regulatory (Treg) cells that are sorted and delivered on day 0 with hematopoietic stem cells, without immunosuppressants, followed 2 days later with infusion of a matching dose of conventional T cells.

“The Treg cells are allowed to expand to create the right microenvironment for the [conventional T cells],” he explained.

In preclinical studies, donor-derived, high-purity Tregs delivered prior to adoptive transfer of conventional T cells prevented GVHD while maintaining graft-versus-tumor immunity, he said.
 

Two T-cell infusions

He reported updated results from current studies on a total of 50 adults, with a cohort of 144 patients treated concurrently with standard of care as controls.

The Orca-T–treated patients had a median age of 47 and 52% were male. Indications for transplant included acute myeloid and acute lymphoblastic leukemia, chronic myeloid leukemia, B-cell lymphoma, myelodysplastic syndrome/myelofibrosis, and other unspecified indications.

In both the Orca-T and control cohorts, patients underwent myeloablative conditioning from 10 to 2 days prior to stem cell infusion.

As noted patients in the experimental arm received infusion of hematopoietic stem/progenitor cells and Tregs, followed 2 days later by conventional T-cell infusion, and, on the day after that, tacrolimus at a target dose of 4.6 ng/mL. The conventional T cells were reserved from donor apheresis and were otherwise unmanipulated prior to infusion into the recipient, Dr. Meyer noted.

Patients in the standard-of-care arm received tacrolimus on the day before standard infusion of the apheresis product, followed by methotrexate prophylaxis on days 1, 3, 6 and 11.

Time to neutrophil engraftment, platelet engraftment, and from day 0 to hospital discharge were all significantly shorter in the Orca-T group, at 12 versus 14 days (P < .0001), 11 vs. 17 days (P < .0001), and 15 vs. 17 days (P = .01) respectively.

At 100 days of follow-up, the rate of grade 2 or greater acute GVHD was 30% among standard-of-care patients versus 10% among Orca-T–treated patients. At 1-year follow-up, respective rates of chronic GVHD were 46% vs. 3%.
 

Safety

“In general, the protocol is extremely well tolerated by our patients. We’ve seen no exceptional infectious disease complications, and we’ve seen no other major complications,” Dr. Meyer said.

Cytomegalovirus prophylaxis was used variably, depending on the center and on the attending physician. Epstein-Barr virus reactivation occurred in eight patients, with one requiring therapy, but there was no biopsy or radiographic evidence of posttransplant lymphoproliferative disorder.

In all, 18% of patients had serious adverse events during the reporting period, all of which resolved. There were no treatment-related deaths in the Orca-T arm, compared with 11% of controls.
 

Engraftment differences explored

In the question-and-answer session following the presentation, Christopher J. Gamper, MD, PhD, from the Johns Hopkins Hospital in Baltimore, told Dr. Meyer that “your outcomes from Orca-T look excellent,” and asked about the cost differential, compared with similar, unmanipulated transplants performed with standard GVHD prophylaxis.

“Is this recovered by lower costs for treatment of GVHD?” he asked.

“I have not done an economic cost analysis of course, and I think others may be looking into this,” Dr. Meyer replied. “Graft engineering can be expensive, although it’s an engineering proposition and one could imagine that the costs will go down substantially over time.”

Session moderator Alan Hanash, MD, PhD, from Memorial Sloan Kettering Cancer Center in New York, commented on the differences in engraftment between the experimental controls arms, and asked Dr. Meyer: “Do you think this is due to the difference in prophylaxis? Absence of methotrexate? Do you think that it could be a direct impact of regulatory T cells on hematopoietic engraftment?”

“Certainly not having methotrexate is beneficial for engraftment, and may account for the differences we see, Dr. Meyer said. “However, it is possible that Tregs could be playing a facilitative role. There certainly is good preclinical literature that Tregs, particularly in the bone marrow space, can facilitate bone marrow engraftment.”

The Orca-T trials are sponsored by Orca Bio and Stanford, with support from the National Institutes of Health. Dr. Meyer receives research support from Orca and is a scientific adviser to GigaGen, Triursus, Incyte, and Indee Labs. Dr. Hanash and Dr. Gamper had no relevant disclosures.

Steroids are usually the first choice of therapy for the treatment of patients with graft-vs.-host disease (GVHD), but complications from steroid use may carry a high financial cost, investigators caution.

Among 689 patients with a diagnosis of GVHD following a hematopoietic stem cell transplant (HSCT) who received steroids, 685 (97%) had at least one steroid-related complication, resulting in nearly $165,000 in mean health-care costs over 24 months, said Elizabeth J. Bell, PhD, MPH, an epidemiologist at Optum Inc.

“For both acute and chronic GVHD, the standard of care for first-line treatment is systemic steroids. The complications associated with steroid treatment are well known. However, the health-care resources utilized and the costs incurred by these patients are not well-quantified,” she said at the Transplantation & Cellular Therapies Meetings (Abstract 12).

Dr. Bell reported the results of a retrospective database analysis on costs associated with steroid complications in HSCT recipients at the meeting, which was held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

She and colleagues from Optum, Incyte, and the University of Minnesota in Minneapolis looked at data on 689 patients with a diagnosis of GVHD after HSCT who received systemic steroids from July 1, 2010, through Aug. 31, 2019. The data were extracted from the Optum Research database, and included U.S. commercial and Medicare Advantage patients.

They looked at total complications and steroid-associated complications in each of four categories: infections; metabolic or endocrine complications (for example, diabetes, dyslipidemia); gastrointestinal (GI) complications (e.g., peptic ulcer disease); and bone or muscle complications (myopathy, etc).

They estimated costs based on International Classification of Diseases (ICD) codes for any steroid complications during the 24 months after steroid initiation, including those complications that may have been present at the time of GVHD diagnosis.

The median patient age was 55 years, and 60% of the sample were male. The mean Charlson Comorbidity Index score at baseline was 3.

Overall, 22% of patients had only acute GVHD, 21% had only chronic GVHD, and 39% had both acute and chronic disease. The GVHD type was unspecified in the remaining 18%.

The median time from GVHD diagnosis to initiating steroids was 30 days for patients with both acute and chronic disease, as well as those with both presentations. The median time to initiation was 36 days for patients with unspecified GVHD type.

The median cumulative duration of steroid use over 24 months was 62 days for patients with acute GVHD, 208 days for those with chronic GVHD, 166 days for those with both, and 74 days for patients with unspecified GVHD type.

As noted before, complications occurred in 97% of patients, with infections being the most common complications, occurring in 80% of patients, followed by metabolic/endocrine complications in 32%, gastrointestinal in 29%, and bone/muscle complications in 20%.

For the 665 patients who had any steroid-related complication, the mean costs of steroid-associated care in the 24 months after they were started on steroids was $164,787, and the median cost was $50,834.

Health care costs were highest among patients with infections, at a mean of $167,473, and a median of $57,680, followed by bone/muscle conditions ($75,289 and $2,057, respectively), GI conditions ($67,861 and $3,360), and metabolic or endocrine conditions ($47, 101 and $1,164).

In all categories, hospitalizations accounted for the large majority of costs.

Two-thirds (66%) of patients who experienced any steroid-related complication required hospitalization, primarily for infections.

Among all patients with complications, the median cumulative hospital stay over 24 months was 20 days, with bone/muscle complications and infections associated with a median of 19 and 18 days of hospitalization, respectively.

Dr. Bell acknowledged that the study was limited by use of ICD coding to identify steroid complication-related health-care utilization and costs, which can be imprecise, and by the fact that the analysis included only complications resulting in health care use as documented in medical claims. In addition, the investigators noted that they could not control for the possibility that steroids exacerbated conditions that existed at baseline.

“These findings emphasize the need to cautiously evaluate the treatment options for patients with GVHD. Future study with medical records is needed to provide insights on the clinical aspects of the complications (e.g., severity and suspected causality),” Dr. Bell and colleagues concluded in the study’s abstract.
 

Definitions questioned

An HSCT specialist approached for comment said that the findings of the study made sense, but she had questions regarding the study methodology.

“I would intuitively think that steroid-associated complications are a major cause of health care use in GVHD patients and it’s interesting to see that there is emerging data to support this hypothesis,” HSCT specialist Hélène Schoemans, MD of the University of Leuven, Belgium, said in an interview.

She noted, however, that “it is surprising that the period of steroid initiation was the same for acute and chronic GVHD,” and questioned whether that anomalous finding could be due to the study’s definition of acute and chronic GVHD or to how the period from baseline to steroid initiation was defined.

The questions about the definitions and timing of therapy make it uncertain as to whether the complications reported were caused by steroids or by some other factor, she suggested.

The study was supported by Optum Inc. Dr. Bell is an employee of the company, and a paid consultant of Incyte. Dr. Schoemans has received travel expenses from Celgene, Abbvie, and Incyte; is part of the advisory boards for Incyte; and has received speakers fees from Novartis, Incyte, Jazz Pharmaceuticals, and Takeda.

Steroids are usually the first choice of therapy for the treatment of patients with graft-vs.-host disease (GVHD), but complications from steroid use may carry a high financial cost, investigators caution.

Among 689 patients with a diagnosis of GVHD following a hematopoietic stem cell transplant (HSCT) who received steroids, 685 (97%) had at least one steroid-related complication, resulting in nearly $165,000 in mean health-care costs over 24 months, said Elizabeth J. Bell, PhD, MPH, an epidemiologist at Optum Inc.

“For both acute and chronic GVHD, the standard of care for first-line treatment is systemic steroids. The complications associated with steroid treatment are well known. However, the health-care resources utilized and the costs incurred by these patients are not well-quantified,” she said at the Transplantation & Cellular Therapies Meetings (Abstract 12).

Dr. Bell reported the results of a retrospective database analysis on costs associated with steroid complications in HSCT recipients at the meeting, which was held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

She and colleagues from Optum, Incyte, and the University of Minnesota in Minneapolis looked at data on 689 patients with a diagnosis of GVHD after HSCT who received systemic steroids from July 1, 2010, through Aug. 31, 2019. The data were extracted from the Optum Research database, and included U.S. commercial and Medicare Advantage patients.

They looked at total complications and steroid-associated complications in each of four categories: infections; metabolic or endocrine complications (for example, diabetes, dyslipidemia); gastrointestinal (GI) complications (e.g., peptic ulcer disease); and bone or muscle complications (myopathy, etc).

They estimated costs based on International Classification of Diseases (ICD) codes for any steroid complications during the 24 months after steroid initiation, including those complications that may have been present at the time of GVHD diagnosis.

The median patient age was 55 years, and 60% of the sample were male. The mean Charlson Comorbidity Index score at baseline was 3.

Overall, 22% of patients had only acute GVHD, 21% had only chronic GVHD, and 39% had both acute and chronic disease. The GVHD type was unspecified in the remaining 18%.

The median time from GVHD diagnosis to initiating steroids was 30 days for patients with both acute and chronic disease, as well as those with both presentations. The median time to initiation was 36 days for patients with unspecified GVHD type.

The median cumulative duration of steroid use over 24 months was 62 days for patients with acute GVHD, 208 days for those with chronic GVHD, 166 days for those with both, and 74 days for patients with unspecified GVHD type.

As noted before, complications occurred in 97% of patients, with infections being the most common complications, occurring in 80% of patients, followed by metabolic/endocrine complications in 32%, gastrointestinal in 29%, and bone/muscle complications in 20%.

For the 665 patients who had any steroid-related complication, the mean costs of steroid-associated care in the 24 months after they were started on steroids was $164,787, and the median cost was $50,834.

Health care costs were highest among patients with infections, at a mean of $167,473, and a median of $57,680, followed by bone/muscle conditions ($75,289 and $2,057, respectively), GI conditions ($67,861 and $3,360), and metabolic or endocrine conditions ($47, 101 and $1,164).

In all categories, hospitalizations accounted for the large majority of costs.

Two-thirds (66%) of patients who experienced any steroid-related complication required hospitalization, primarily for infections.

Among all patients with complications, the median cumulative hospital stay over 24 months was 20 days, with bone/muscle complications and infections associated with a median of 19 and 18 days of hospitalization, respectively.

Dr. Bell acknowledged that the study was limited by use of ICD coding to identify steroid complication-related health-care utilization and costs, which can be imprecise, and by the fact that the analysis included only complications resulting in health care use as documented in medical claims. In addition, the investigators noted that they could not control for the possibility that steroids exacerbated conditions that existed at baseline.

“These findings emphasize the need to cautiously evaluate the treatment options for patients with GVHD. Future study with medical records is needed to provide insights on the clinical aspects of the complications (e.g., severity and suspected causality),” Dr. Bell and colleagues concluded in the study’s abstract.
 

Definitions questioned

An HSCT specialist approached for comment said that the findings of the study made sense, but she had questions regarding the study methodology.

“I would intuitively think that steroid-associated complications are a major cause of health care use in GVHD patients and it’s interesting to see that there is emerging data to support this hypothesis,” HSCT specialist Hélène Schoemans, MD of the University of Leuven, Belgium, said in an interview.

She noted, however, that “it is surprising that the period of steroid initiation was the same for acute and chronic GVHD,” and questioned whether that anomalous finding could be due to the study’s definition of acute and chronic GVHD or to how the period from baseline to steroid initiation was defined.

The questions about the definitions and timing of therapy make it uncertain as to whether the complications reported were caused by steroids or by some other factor, she suggested.

The study was supported by Optum Inc. Dr. Bell is an employee of the company, and a paid consultant of Incyte. Dr. Schoemans has received travel expenses from Celgene, Abbvie, and Incyte; is part of the advisory boards for Incyte; and has received speakers fees from Novartis, Incyte, Jazz Pharmaceuticals, and Takeda.

Steroids are usually the first choice of therapy for the treatment of patients with graft-vs.-host disease (GVHD), but complications from steroid use may carry a high financial cost, investigators caution.

Among 689 patients with a diagnosis of GVHD following a hematopoietic stem cell transplant (HSCT) who received steroids, 685 (97%) had at least one steroid-related complication, resulting in nearly $165,000 in mean health-care costs over 24 months, said Elizabeth J. Bell, PhD, MPH, an epidemiologist at Optum Inc.

“For both acute and chronic GVHD, the standard of care for first-line treatment is systemic steroids. The complications associated with steroid treatment are well known. However, the health-care resources utilized and the costs incurred by these patients are not well-quantified,” she said at the Transplantation & Cellular Therapies Meetings (Abstract 12).

Dr. Bell reported the results of a retrospective database analysis on costs associated with steroid complications in HSCT recipients at the meeting, which was held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

She and colleagues from Optum, Incyte, and the University of Minnesota in Minneapolis looked at data on 689 patients with a diagnosis of GVHD after HSCT who received systemic steroids from July 1, 2010, through Aug. 31, 2019. The data were extracted from the Optum Research database, and included U.S. commercial and Medicare Advantage patients.

They looked at total complications and steroid-associated complications in each of four categories: infections; metabolic or endocrine complications (for example, diabetes, dyslipidemia); gastrointestinal (GI) complications (e.g., peptic ulcer disease); and bone or muscle complications (myopathy, etc).

They estimated costs based on International Classification of Diseases (ICD) codes for any steroid complications during the 24 months after steroid initiation, including those complications that may have been present at the time of GVHD diagnosis.

The median patient age was 55 years, and 60% of the sample were male. The mean Charlson Comorbidity Index score at baseline was 3.

Overall, 22% of patients had only acute GVHD, 21% had only chronic GVHD, and 39% had both acute and chronic disease. The GVHD type was unspecified in the remaining 18%.

The median time from GVHD diagnosis to initiating steroids was 30 days for patients with both acute and chronic disease, as well as those with both presentations. The median time to initiation was 36 days for patients with unspecified GVHD type.

The median cumulative duration of steroid use over 24 months was 62 days for patients with acute GVHD, 208 days for those with chronic GVHD, 166 days for those with both, and 74 days for patients with unspecified GVHD type.

As noted before, complications occurred in 97% of patients, with infections being the most common complications, occurring in 80% of patients, followed by metabolic/endocrine complications in 32%, gastrointestinal in 29%, and bone/muscle complications in 20%.

For the 665 patients who had any steroid-related complication, the mean costs of steroid-associated care in the 24 months after they were started on steroids was $164,787, and the median cost was $50,834.

Health care costs were highest among patients with infections, at a mean of $167,473, and a median of $57,680, followed by bone/muscle conditions ($75,289 and $2,057, respectively), GI conditions ($67,861 and $3,360), and metabolic or endocrine conditions ($47, 101 and $1,164).

In all categories, hospitalizations accounted for the large majority of costs.

Two-thirds (66%) of patients who experienced any steroid-related complication required hospitalization, primarily for infections.

Among all patients with complications, the median cumulative hospital stay over 24 months was 20 days, with bone/muscle complications and infections associated with a median of 19 and 18 days of hospitalization, respectively.

Dr. Bell acknowledged that the study was limited by use of ICD coding to identify steroid complication-related health-care utilization and costs, which can be imprecise, and by the fact that the analysis included only complications resulting in health care use as documented in medical claims. In addition, the investigators noted that they could not control for the possibility that steroids exacerbated conditions that existed at baseline.

“These findings emphasize the need to cautiously evaluate the treatment options for patients with GVHD. Future study with medical records is needed to provide insights on the clinical aspects of the complications (e.g., severity and suspected causality),” Dr. Bell and colleagues concluded in the study’s abstract.
 

Definitions questioned

An HSCT specialist approached for comment said that the findings of the study made sense, but she had questions regarding the study methodology.

“I would intuitively think that steroid-associated complications are a major cause of health care use in GVHD patients and it’s interesting to see that there is emerging data to support this hypothesis,” HSCT specialist Hélène Schoemans, MD of the University of Leuven, Belgium, said in an interview.

She noted, however, that “it is surprising that the period of steroid initiation was the same for acute and chronic GVHD,” and questioned whether that anomalous finding could be due to the study’s definition of acute and chronic GVHD or to how the period from baseline to steroid initiation was defined.

The questions about the definitions and timing of therapy make it uncertain as to whether the complications reported were caused by steroids or by some other factor, she suggested.

The study was supported by Optum Inc. Dr. Bell is an employee of the company, and a paid consultant of Incyte. Dr. Schoemans has received travel expenses from Celgene, Abbvie, and Incyte; is part of the advisory boards for Incyte; and has received speakers fees from Novartis, Incyte, Jazz Pharmaceuticals, and Takeda.

Despite improvements in prevention of graft-versus-host disease, chronic GVHD still occurs in 10%-50% of patients who undergo an allogeneic hematopoietic stem cell transplant, and these patients may require prolonged treatment with multiple lines of therapy, said a hematologist and transplant researcher.

“More effective, less toxic therapies for chronic GVHD are needed,” Stephanie Lee, MD, MPH, from the Fred Hutchinson Cancer Research Center in Seattle said at the Transplant & Cellular Therapies Meetings.

Dr. Lee reviewed clinical trials for chronic GVHD at the meeting held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

Although the incidence of chronic GVHD has gradually declined over the last 40 years and both relapse-free and overall survival following a chronic GVHD diagnosis have improved, “for patients who are diagnosed with chronic GVHD, they still will see many lines of therapy and many years of therapy,” she said.

Among 148 patients with chronic GVHD treated at her center, for example, 66% went on to two lines of therapy, 50% went on to three lines, 37% required four lines of therapy, and 20% needed five lines or more.

Salvage therapies for patients with chronic GVHD have evolved away from immunomodulators and immunosuppressants in the early 1990s, toward monoclonal antibodies such as rituximab in the early 2000s, to interleukin-2 and to tyrosine kinase inhibitors such as ruxolitinib (Jakafi) and ibrutinib (Imbruvica).

There are currently 36 agents that are FDA approved for at least one indication and can also be prescribed for the treatment of chronic GVHD, Dr. Lee noted.
 

Treatment goals

Dr. Lee laid out six goals for treating patients with chronic GVHD. They include:

• Controlling current signs and symptoms, measured by response rates and patient-reported outcomes
• Preventing further tissue and organ damage
• Minimizing toxicity
• Maintaining graft-versus-tumor effect
• Achieving graft tolerance and stopping immunosuppression
• Decreasing nonrelapse mortality and improving survival

Active trials

Dr. Lee identified 33 trials with chronic GVHD as an indication that are currently recruiting, and an additional 13 trials that are active but closed to recruiting. The trials can be generally grouped by mechanism of action, and involve agents targeting T-regulatory cells, B cells and/or B-cell receptor (BCR) signaling, monocytes/macrophages, costimulatory blockage, a proteasome inhibition, Janus kinase (JAK) 1/2 inhibitors, ROCK2 inhibitors, hedgehog pathway inhibition, cellular therapy, and organ-targeted therapy.

Most of the trials have overall response rate as the primary endpoint, and all but five are currently in phase 1 or 2. The currently active phase 3 trials include two with ibrutinib, one with the investigational agent itacitinib, one with ruxolitinib, and one with mesenchymal stem cells.

“I’ll note that, when results are reported, the denominator really matters for the overall response rate, especially if you’re talking about small trials, because if you require the patient to be treated with an agent for a certain period of time, and you take out all the people who didn’t make it to that time point, then your overall response rate looks better,” she said.
 

BTK inhibitors

The first-in-class Bruton tyrosine kinase (BTK) inhibitor ibrutinib was the first and thus far only agent approved by the Food and Drug Administration for chronic GVHD. The approval was based on a single-arm, multicenter trial with 42 patients.

The ORR in this trial was 69%, consisting of 31% complete responses and 38% partial responses, with a duration of response longer than 10 months in slightly more than half of all patients. In all, 24% of patients had improvement of symptoms in two consecutive visits, and 29% continued on ibrutinib at the time of the primary analysis in 2017.

Based on these promising results, acalabrutinib, which is more potent and selective for BTK than ibrutinib, with no effect on either platelets or natural killer cells, is currently under investigation in a phase 2 trial in 50 patients at a dose of 100 mg orally twice daily.
 

JAK1/2 inhibition

The JAK1 inhibitor itacitinib failed to meet its primary ORR endpoint in the phase 3 GRAVITAS-301 study, according to a press release, but the manufacturer (Incyte) said that it is continuing its commitment to JAK inhibitors with ruxolitinib, which has shown activity against acute, steroid-refractory GVHD, and is being explored for prevention of chronic GVHD in the randomized, phase 3 REACH3 study.

The trial met its primary endpoint for a higher ORR at week 24 with ruxolitinib versus best available therapy, at 49.7% versus 25.6%, respectively, which translated into an odds ratio for response with the JAK inhibitor of 2.99 (P < .0001).
 

Selective T-cell expansion

Efavaleukin alfa is an IL-2-mutated protein (mutein), with a mutation in the IL-2RB-binding portion of IL-2 causing increased selectivity for regulatory T-cell expansion. It is bound to an IgG-Fc domain that is itself mutated, with reduced Fc receptor binding and IgG effector function to give it a longer half life. This agent is being studied in a phase 1/2 trial in a subcutaneous formulation delivered every 1 or 2 weeks to 68 patients.

Monocyte/macrophage depletion

Axatilimab is a high-affinity antibody targeting colony stimulating factor–1 receptor (CSF-1R) expressed on monocytes and macrophages. By blocking CSF-1R, it depletes circulation of nonclassical monocytes and prevents the differentiation and survival of M2 macrophages in tissue.

It is currently being investigated 30 patients in a phase 1/2 study in an intravenous formulation delivered over 30 minutes every 2-4 weeks.
 

Hedgehog pathway inhibition

There is evidence suggesting that hedgehog pathway inhibition can lessen fibrosis. Glasdegib (Daurismo) a potent selective oral inhibitor of the hedgehog signaling pathway, is approved for use with low-dose cytarabine for patients with newly diagnosed acute myeloid leukemia aged older than 75 years or have comorbidities precluding intensive chemotherapy.

This agent is associated with drug intolerance because of muscle spasms, dysgeusia, and alopecia, however.

The drug is currently in phase 1/2 at a dose of 50 mg orally per day in 20 patients.
 

ROCK2 inhibition

Belumosudil (formerly KD025) “appears to rebalance the immune system,” Dr. Lee said. Investigators think that the drug dampens an autoaggressive inflammatory response by selective inhibition of ROCK2.

This drug has been studied in a dose-escalation study and a phase 2 trial, in which 132 participants were randomized to receive belumosudil 200 mg either once or twice daily.

At a median follow-up of 8 months, the ORR with belumosudil 200 mg once and twice daily was 73% and 74%, respectively. Similar results were seen in patients who had previously received either ruxolitinib or ibrutinib. High response rates were seen in patients with severe chronic GVHD, involvement of four or more organs and a refractory response to their last line of therapy.
 

Hard-to-manage patients

“We’re very hopeful for many of these agents, but we have to acknowledge that there are still many management dilemmas, patients that we just don’t really know what to do with,” Dr. Lee said. “These include patients who have bad sclerosis and fasciitis, nonhealing skin ulcers, bronchiolitis obliterans, serositis that can be very difficult to manage, severe keratoconjunctivitis that can be eyesight threatening, nonhealing mouth ulcers, esophageal structures, and always patients who have frequent infections.

“We are hopeful that some these agents will be useful for our patients who have severe manifestations, but often the number of patients with these manifestations in the trials is too low to say something specific about them,” she added.
 

‘Exciting time’

“It’s an exciting time because there are a lot of different drugs that are being studied for chronic GVHD,” commented Betty Hamilton, MD, a hematologist/oncologist at the Cleveland Clinic.

“I think that where the field is going in terms of treatment is recognizing that chronic GVHD is a pretty heterogeneous disease, and we have to learn even more about the underlying biologic pathways to be able to determine which class of drugs to use and when,” she said in an interview.

She agreed with Dr. Lee that the goals of treating patients with chronic GVHD include improving symptoms and quality, preventing progression, ideally tapering patients off immunosuppression, and achieving a balance between preventing negative consequences of GVHD while maintain the benefits of a graft-versus-leukemia effect.

“In our center, drug choice is based on physician preference and comfort with how often they’ve used the drug, patients’ comorbidities, toxicities of the drug, and logistical considerations,” Dr. Hamilton said.

Dr. Lee disclosed consulting activities for Pfizer and Kadmon, travel and lodging from Amgen, and research funding from those companies and others. Dr. Hamilton disclosed consulting for Syndax and Incyte.

Despite improvements in prevention of graft-versus-host disease, chronic GVHD still occurs in 10%-50% of patients who undergo an allogeneic hematopoietic stem cell transplant, and these patients may require prolonged treatment with multiple lines of therapy, said a hematologist and transplant researcher.

“More effective, less toxic therapies for chronic GVHD are needed,” Stephanie Lee, MD, MPH, from the Fred Hutchinson Cancer Research Center in Seattle said at the Transplant & Cellular Therapies Meetings.

Dr. Lee reviewed clinical trials for chronic GVHD at the meeting held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

Although the incidence of chronic GVHD has gradually declined over the last 40 years and both relapse-free and overall survival following a chronic GVHD diagnosis have improved, “for patients who are diagnosed with chronic GVHD, they still will see many lines of therapy and many years of therapy,” she said.

Among 148 patients with chronic GVHD treated at her center, for example, 66% went on to two lines of therapy, 50% went on to three lines, 37% required four lines of therapy, and 20% needed five lines or more.

Salvage therapies for patients with chronic GVHD have evolved away from immunomodulators and immunosuppressants in the early 1990s, toward monoclonal antibodies such as rituximab in the early 2000s, to interleukin-2 and to tyrosine kinase inhibitors such as ruxolitinib (Jakafi) and ibrutinib (Imbruvica).

There are currently 36 agents that are FDA approved for at least one indication and can also be prescribed for the treatment of chronic GVHD, Dr. Lee noted.
 

Treatment goals

Dr. Lee laid out six goals for treating patients with chronic GVHD. They include:

• Controlling current signs and symptoms, measured by response rates and patient-reported outcomes
• Preventing further tissue and organ damage
• Minimizing toxicity
• Maintaining graft-versus-tumor effect
• Achieving graft tolerance and stopping immunosuppression
• Decreasing nonrelapse mortality and improving survival

Active trials

Dr. Lee identified 33 trials with chronic GVHD as an indication that are currently recruiting, and an additional 13 trials that are active but closed to recruiting. The trials can be generally grouped by mechanism of action, and involve agents targeting T-regulatory cells, B cells and/or B-cell receptor (BCR) signaling, monocytes/macrophages, costimulatory blockage, a proteasome inhibition, Janus kinase (JAK) 1/2 inhibitors, ROCK2 inhibitors, hedgehog pathway inhibition, cellular therapy, and organ-targeted therapy.

Most of the trials have overall response rate as the primary endpoint, and all but five are currently in phase 1 or 2. The currently active phase 3 trials include two with ibrutinib, one with the investigational agent itacitinib, one with ruxolitinib, and one with mesenchymal stem cells.

“I’ll note that, when results are reported, the denominator really matters for the overall response rate, especially if you’re talking about small trials, because if you require the patient to be treated with an agent for a certain period of time, and you take out all the people who didn’t make it to that time point, then your overall response rate looks better,” she said.
 

BTK inhibitors

The first-in-class Bruton tyrosine kinase (BTK) inhibitor ibrutinib was the first and thus far only agent approved by the Food and Drug Administration for chronic GVHD. The approval was based on a single-arm, multicenter trial with 42 patients.

The ORR in this trial was 69%, consisting of 31% complete responses and 38% partial responses, with a duration of response longer than 10 months in slightly more than half of all patients. In all, 24% of patients had improvement of symptoms in two consecutive visits, and 29% continued on ibrutinib at the time of the primary analysis in 2017.

Based on these promising results, acalabrutinib, which is more potent and selective for BTK than ibrutinib, with no effect on either platelets or natural killer cells, is currently under investigation in a phase 2 trial in 50 patients at a dose of 100 mg orally twice daily.
 

JAK1/2 inhibition

The JAK1 inhibitor itacitinib failed to meet its primary ORR endpoint in the phase 3 GRAVITAS-301 study, according to a press release, but the manufacturer (Incyte) said that it is continuing its commitment to JAK inhibitors with ruxolitinib, which has shown activity against acute, steroid-refractory GVHD, and is being explored for prevention of chronic GVHD in the randomized, phase 3 REACH3 study.

The trial met its primary endpoint for a higher ORR at week 24 with ruxolitinib versus best available therapy, at 49.7% versus 25.6%, respectively, which translated into an odds ratio for response with the JAK inhibitor of 2.99 (P < .0001).
 

Selective T-cell expansion

Efavaleukin alfa is an IL-2-mutated protein (mutein), with a mutation in the IL-2RB-binding portion of IL-2 causing increased selectivity for regulatory T-cell expansion. It is bound to an IgG-Fc domain that is itself mutated, with reduced Fc receptor binding and IgG effector function to give it a longer half life. This agent is being studied in a phase 1/2 trial in a subcutaneous formulation delivered every 1 or 2 weeks to 68 patients.

Monocyte/macrophage depletion

Axatilimab is a high-affinity antibody targeting colony stimulating factor–1 receptor (CSF-1R) expressed on monocytes and macrophages. By blocking CSF-1R, it depletes circulation of nonclassical monocytes and prevents the differentiation and survival of M2 macrophages in tissue.

It is currently being investigated 30 patients in a phase 1/2 study in an intravenous formulation delivered over 30 minutes every 2-4 weeks.
 

Hedgehog pathway inhibition

There is evidence suggesting that hedgehog pathway inhibition can lessen fibrosis. Glasdegib (Daurismo) a potent selective oral inhibitor of the hedgehog signaling pathway, is approved for use with low-dose cytarabine for patients with newly diagnosed acute myeloid leukemia aged older than 75 years or have comorbidities precluding intensive chemotherapy.

This agent is associated with drug intolerance because of muscle spasms, dysgeusia, and alopecia, however.

The drug is currently in phase 1/2 at a dose of 50 mg orally per day in 20 patients.
 

ROCK2 inhibition

Belumosudil (formerly KD025) “appears to rebalance the immune system,” Dr. Lee said. Investigators think that the drug dampens an autoaggressive inflammatory response by selective inhibition of ROCK2.

This drug has been studied in a dose-escalation study and a phase 2 trial, in which 132 participants were randomized to receive belumosudil 200 mg either once or twice daily.

At a median follow-up of 8 months, the ORR with belumosudil 200 mg once and twice daily was 73% and 74%, respectively. Similar results were seen in patients who had previously received either ruxolitinib or ibrutinib. High response rates were seen in patients with severe chronic GVHD, involvement of four or more organs and a refractory response to their last line of therapy.
 

Hard-to-manage patients

“We’re very hopeful for many of these agents, but we have to acknowledge that there are still many management dilemmas, patients that we just don’t really know what to do with,” Dr. Lee said. “These include patients who have bad sclerosis and fasciitis, nonhealing skin ulcers, bronchiolitis obliterans, serositis that can be very difficult to manage, severe keratoconjunctivitis that can be eyesight threatening, nonhealing mouth ulcers, esophageal structures, and always patients who have frequent infections.

“We are hopeful that some these agents will be useful for our patients who have severe manifestations, but often the number of patients with these manifestations in the trials is too low to say something specific about them,” she added.
 

‘Exciting time’

“It’s an exciting time because there are a lot of different drugs that are being studied for chronic GVHD,” commented Betty Hamilton, MD, a hematologist/oncologist at the Cleveland Clinic.

“I think that where the field is going in terms of treatment is recognizing that chronic GVHD is a pretty heterogeneous disease, and we have to learn even more about the underlying biologic pathways to be able to determine which class of drugs to use and when,” she said in an interview.

She agreed with Dr. Lee that the goals of treating patients with chronic GVHD include improving symptoms and quality, preventing progression, ideally tapering patients off immunosuppression, and achieving a balance between preventing negative consequences of GVHD while maintain the benefits of a graft-versus-leukemia effect.

“In our center, drug choice is based on physician preference and comfort with how often they’ve used the drug, patients’ comorbidities, toxicities of the drug, and logistical considerations,” Dr. Hamilton said.

Dr. Lee disclosed consulting activities for Pfizer and Kadmon, travel and lodging from Amgen, and research funding from those companies and others. Dr. Hamilton disclosed consulting for Syndax and Incyte.

Despite improvements in prevention of graft-versus-host disease, chronic GVHD still occurs in 10%-50% of patients who undergo an allogeneic hematopoietic stem cell transplant, and these patients may require prolonged treatment with multiple lines of therapy, said a hematologist and transplant researcher.

“More effective, less toxic therapies for chronic GVHD are needed,” Stephanie Lee, MD, MPH, from the Fred Hutchinson Cancer Research Center in Seattle said at the Transplant & Cellular Therapies Meetings.

Dr. Lee reviewed clinical trials for chronic GVHD at the meeting held by the American Society for Blood and Marrow Transplantation and the Center for International Blood and Marrow Transplant Research.

Although the incidence of chronic GVHD has gradually declined over the last 40 years and both relapse-free and overall survival following a chronic GVHD diagnosis have improved, “for patients who are diagnosed with chronic GVHD, they still will see many lines of therapy and many years of therapy,” she said.

Among 148 patients with chronic GVHD treated at her center, for example, 66% went on to two lines of therapy, 50% went on to three lines, 37% required four lines of therapy, and 20% needed five lines or more.

Salvage therapies for patients with chronic GVHD have evolved away from immunomodulators and immunosuppressants in the early 1990s, toward monoclonal antibodies such as rituximab in the early 2000s, to interleukin-2 and to tyrosine kinase inhibitors such as ruxolitinib (Jakafi) and ibrutinib (Imbruvica).

There are currently 36 agents that are FDA approved for at least one indication and can also be prescribed for the treatment of chronic GVHD, Dr. Lee noted.
 

Treatment goals

Dr. Lee laid out six goals for treating patients with chronic GVHD. They include:

• Controlling current signs and symptoms, measured by response rates and patient-reported outcomes
• Preventing further tissue and organ damage
• Minimizing toxicity
• Maintaining graft-versus-tumor effect
• Achieving graft tolerance and stopping immunosuppression
• Decreasing nonrelapse mortality and improving survival

Active trials

Dr. Lee identified 33 trials with chronic GVHD as an indication that are currently recruiting, and an additional 13 trials that are active but closed to recruiting. The trials can be generally grouped by mechanism of action, and involve agents targeting T-regulatory cells, B cells and/or B-cell receptor (BCR) signaling, monocytes/macrophages, costimulatory blockage, a proteasome inhibition, Janus kinase (JAK) 1/2 inhibitors, ROCK2 inhibitors, hedgehog pathway inhibition, cellular therapy, and organ-targeted therapy.

Most of the trials have overall response rate as the primary endpoint, and all but five are currently in phase 1 or 2. The currently active phase 3 trials include two with ibrutinib, one with the investigational agent itacitinib, one with ruxolitinib, and one with mesenchymal stem cells.

“I’ll note that, when results are reported, the denominator really matters for the overall response rate, especially if you’re talking about small trials, because if you require the patient to be treated with an agent for a certain period of time, and you take out all the people who didn’t make it to that time point, then your overall response rate looks better,” she said.
 

BTK inhibitors

The first-in-class Bruton tyrosine kinase (BTK) inhibitor ibrutinib was the first and thus far only agent approved by the Food and Drug Administration for chronic GVHD. The approval was based on a single-arm, multicenter trial with 42 patients.

The ORR in this trial was 69%, consisting of 31% complete responses and 38% partial responses, with a duration of response longer than 10 months in slightly more than half of all patients. In all, 24% of patients had improvement of symptoms in two consecutive visits, and 29% continued on ibrutinib at the time of the primary analysis in 2017.

Based on these promising results, acalabrutinib, which is more potent and selective for BTK than ibrutinib, with no effect on either platelets or natural killer cells, is currently under investigation in a phase 2 trial in 50 patients at a dose of 100 mg orally twice daily.
 

JAK1/2 inhibition

The JAK1 inhibitor itacitinib failed to meet its primary ORR endpoint in the phase 3 GRAVITAS-301 study, according to a press release, but the manufacturer (Incyte) said that it is continuing its commitment to JAK inhibitors with ruxolitinib, which has shown activity against acute, steroid-refractory GVHD, and is being explored for prevention of chronic GVHD in the randomized, phase 3 REACH3 study.

The trial met its primary endpoint for a higher ORR at week 24 with ruxolitinib versus best available therapy, at 49.7% versus 25.6%, respectively, which translated into an odds ratio for response with the JAK inhibitor of 2.99 (P < .0001).
 

Selective T-cell expansion

Efavaleukin alfa is an IL-2-mutated protein (mutein), with a mutation in the IL-2RB-binding portion of IL-2 causing increased selectivity for regulatory T-cell expansion. It is bound to an IgG-Fc domain that is itself mutated, with reduced Fc receptor binding and IgG effector function to give it a longer half life. This agent is being studied in a phase 1/2 trial in a subcutaneous formulation delivered every 1 or 2 weeks to 68 patients.

Monocyte/macrophage depletion

Axatilimab is a high-affinity antibody targeting colony stimulating factor–1 receptor (CSF-1R) expressed on monocytes and macrophages. By blocking CSF-1R, it depletes circulation of nonclassical monocytes and prevents the differentiation and survival of M2 macrophages in tissue.

It is currently being investigated 30 patients in a phase 1/2 study in an intravenous formulation delivered over 30 minutes every 2-4 weeks.
 

Hedgehog pathway inhibition

There is evidence suggesting that hedgehog pathway inhibition can lessen fibrosis. Glasdegib (Daurismo) a potent selective oral inhibitor of the hedgehog signaling pathway, is approved for use with low-dose cytarabine for patients with newly diagnosed acute myeloid leukemia aged older than 75 years or have comorbidities precluding intensive chemotherapy.

This agent is associated with drug intolerance because of muscle spasms, dysgeusia, and alopecia, however.

The drug is currently in phase 1/2 at a dose of 50 mg orally per day in 20 patients.
 

ROCK2 inhibition

Belumosudil (formerly KD025) “appears to rebalance the immune system,” Dr. Lee said. Investigators think that the drug dampens an autoaggressive inflammatory response by selective inhibition of ROCK2.

This drug has been studied in a dose-escalation study and a phase 2 trial, in which 132 participants were randomized to receive belumosudil 200 mg either once or twice daily.

At a median follow-up of 8 months, the ORR with belumosudil 200 mg once and twice daily was 73% and 74%, respectively. Similar results were seen in patients who had previously received either ruxolitinib or ibrutinib. High response rates were seen in patients with severe chronic GVHD, involvement of four or more organs and a refractory response to their last line of therapy.
 

Hard-to-manage patients

“We’re very hopeful for many of these agents, but we have to acknowledge that there are still many management dilemmas, patients that we just don’t really know what to do with,” Dr. Lee said. “These include patients who have bad sclerosis and fasciitis, nonhealing skin ulcers, bronchiolitis obliterans, serositis that can be very difficult to manage, severe keratoconjunctivitis that can be eyesight threatening, nonhealing mouth ulcers, esophageal structures, and always patients who have frequent infections.

“We are hopeful that some these agents will be useful for our patients who have severe manifestations, but often the number of patients with these manifestations in the trials is too low to say something specific about them,” she added.
 

‘Exciting time’

“It’s an exciting time because there are a lot of different drugs that are being studied for chronic GVHD,” commented Betty Hamilton, MD, a hematologist/oncologist at the Cleveland Clinic.

“I think that where the field is going in terms of treatment is recognizing that chronic GVHD is a pretty heterogeneous disease, and we have to learn even more about the underlying biologic pathways to be able to determine which class of drugs to use and when,” she said in an interview.

She agreed with Dr. Lee that the goals of treating patients with chronic GVHD include improving symptoms and quality, preventing progression, ideally tapering patients off immunosuppression, and achieving a balance between preventing negative consequences of GVHD while maintain the benefits of a graft-versus-leukemia effect.

“In our center, drug choice is based on physician preference and comfort with how often they’ve used the drug, patients’ comorbidities, toxicities of the drug, and logistical considerations,” Dr. Hamilton said.

Dr. Lee disclosed consulting activities for Pfizer and Kadmon, travel and lodging from Amgen, and research funding from those companies and others. Dr. Hamilton disclosed consulting for Syndax and Incyte.

For now at least, total body irradiation (TBI) plus etoposide remains the conditioning regimen of choice for children undergoing allogeneic hematopoietic stem cell transplant for acute lymphoblastic leukemia (ALL), according to an open-label, phase 3 trial from Europe.

The investigators sought to answer a question many physicians have raised: With improvements in human leukocyte antigen typing, better graft-versus-host disease prophylaxis, and other advances, can myeloablative chemotherapy conditioning replace TBI, which is more toxic?

The downstream effects of TBI can include secondary malignancies and cataracts, as well as impaired growth and impaired gonadal and cognitive function.

But the answer to that question is no, or at least, not yet.

The phase 3 trial included individuals with ALL who were aged 4-21 years at time of transplant. They were randomly assigned to receive either fractionated TBI at 12 Gy plus etoposide or chemotherapy based on a myeloablative regimen: fludarabine, thiotepa, and either busulfan or treosulfan.

The trial was stopped after 413 patients had undergone randomization – quite a bit short of the 1,000-patient goal. The trial was terminated because TBI proved clearly superior on an interim analysis at a median follow-up of 2.1 years.

The results showed that 72% of the TBI group – but only 51% of the chemotherapy arm – were relapse free at 2 years with no graft-versus-host disease (P = .0003).

The 2-year treatment-related mortality rate was 2% in the TBI group but 9% with chemotherapy conditioning (P = .03).

The study was published Feb. 1, 2020, in the Journal of Clinical Oncology.

“We recommend TBI plus etoposide conditioning for patients [aged over] 4 years old with high-risk ALL undergoing allogeneic HSCT [hematopoietic stem cell transplant],” they concluded. The investigators were led by Christina Peters, MD, a pediatrics professor at the St. Anna Children’s Cancer Research Institute, Vienna.

The benefits of TBI held on multivariate analysis and across subgroups, including children in their first and second remissions and among those with high-risk cytogenetics. Relapse risk factors, such as age at transplant, leukemic phenotype, and molecular aberrations, did not significantly affect outcomes, the authors reported.

Given that relapses plateaued with TBI at 2.5 years but were still on the upswing for patients who underwent chemoconditioning, “it is unlikely that secondary malignancies after TBI could jeopardize the survival advantage,” they wrote.

“So does this mean that the HCT community is forever chained to TBI as a standard of care? Certainly, it means that without very sound rationale to deviate, a TBI-based preparative regimen is the preferred therapy at present,” Michael Pulsipher, MD, head of blood and marrow transplantation at Children’s Hospital Los Angeles, commented in an accompanying editorial.

However, “there are approaches under study currently that may define patients who do not need TBI for high rates of cure,” he suggested. Those approaches include selecting patients with the deepest remissions and using KIR-favorable haplotype to harness natural killer cell activity.

“In our new world of chimeric antigen receptor T-cells and immunotherapies, surely we can find safer paths to success,” Dr. Pulsipher wrote.

With regard to patient selection, the investigators noted that a recent review that included more than 3,000 children with ALL found no overall survival benefit with TBI versus chemoconditioning for patients in first complete remission but worse outcomes with chemoconditioning among patients in second complete remission. “A similar trend was observed in our subgroup analyses; however, our study was not powered to assess statistical significance in a sample size of 413 patients,” they wrote.

Minimal residual disease did not influence survival outcomes, probably because the investigators were aggressive in inducing deep remission in their patients before transplant, so for most patients, MRD was undetectable or very low beforehand.

The study was funded by Amgen, Jazz Pharmaceuticals, Neovii, Medac, and others. Dr. Peters and coauthors, as well as Dr. Pulsipher have disclosed numerous ties with those and/or other companies.

A version of this article first appeared on Medscape.com.

For now at least, total body irradiation (TBI) plus etoposide remains the conditioning regimen of choice for children undergoing allogeneic hematopoietic stem cell transplant for acute lymphoblastic leukemia (ALL), according to an open-label, phase 3 trial from Europe.

The investigators sought to answer a question many physicians have raised: With improvements in human leukocyte antigen typing, better graft-versus-host disease prophylaxis, and other advances, can myeloablative chemotherapy conditioning replace TBI, which is more toxic?

The downstream effects of TBI can include secondary malignancies and cataracts, as well as impaired growth and impaired gonadal and cognitive function.

But the answer to that question is no, or at least, not yet.

The phase 3 trial included individuals with ALL who were aged 4-21 years at time of transplant. They were randomly assigned to receive either fractionated TBI at 12 Gy plus etoposide or chemotherapy based on a myeloablative regimen: fludarabine, thiotepa, and either busulfan or treosulfan.

The trial was stopped after 413 patients had undergone randomization – quite a bit short of the 1,000-patient goal. The trial was terminated because TBI proved clearly superior on an interim analysis at a median follow-up of 2.1 years.

The results showed that 72% of the TBI group – but only 51% of the chemotherapy arm – were relapse free at 2 years with no graft-versus-host disease (P = .0003).

The 2-year treatment-related mortality rate was 2% in the TBI group but 9% with chemotherapy conditioning (P = .03).

The study was published Feb. 1, 2020, in the Journal of Clinical Oncology.

“We recommend TBI plus etoposide conditioning for patients [aged over] 4 years old with high-risk ALL undergoing allogeneic HSCT [hematopoietic stem cell transplant],” they concluded. The investigators were led by Christina Peters, MD, a pediatrics professor at the St. Anna Children’s Cancer Research Institute, Vienna.

The benefits of TBI held on multivariate analysis and across subgroups, including children in their first and second remissions and among those with high-risk cytogenetics. Relapse risk factors, such as age at transplant, leukemic phenotype, and molecular aberrations, did not significantly affect outcomes, the authors reported.

Given that relapses plateaued with TBI at 2.5 years but were still on the upswing for patients who underwent chemoconditioning, “it is unlikely that secondary malignancies after TBI could jeopardize the survival advantage,” they wrote.

“So does this mean that the HCT community is forever chained to TBI as a standard of care? Certainly, it means that without very sound rationale to deviate, a TBI-based preparative regimen is the preferred therapy at present,” Michael Pulsipher, MD, head of blood and marrow transplantation at Children’s Hospital Los Angeles, commented in an accompanying editorial.

However, “there are approaches under study currently that may define patients who do not need TBI for high rates of cure,” he suggested. Those approaches include selecting patients with the deepest remissions and using KIR-favorable haplotype to harness natural killer cell activity.

“In our new world of chimeric antigen receptor T-cells and immunotherapies, surely we can find safer paths to success,” Dr. Pulsipher wrote.

With regard to patient selection, the investigators noted that a recent review that included more than 3,000 children with ALL found no overall survival benefit with TBI versus chemoconditioning for patients in first complete remission but worse outcomes with chemoconditioning among patients in second complete remission. “A similar trend was observed in our subgroup analyses; however, our study was not powered to assess statistical significance in a sample size of 413 patients,” they wrote.

Minimal residual disease did not influence survival outcomes, probably because the investigators were aggressive in inducing deep remission in their patients before transplant, so for most patients, MRD was undetectable or very low beforehand.

The study was funded by Amgen, Jazz Pharmaceuticals, Neovii, Medac, and others. Dr. Peters and coauthors, as well as Dr. Pulsipher have disclosed numerous ties with those and/or other companies.

A version of this article first appeared on Medscape.com.

For now at least, total body irradiation (TBI) plus etoposide remains the conditioning regimen of choice for children undergoing allogeneic hematopoietic stem cell transplant for acute lymphoblastic leukemia (ALL), according to an open-label, phase 3 trial from Europe.

The investigators sought to answer a question many physicians have raised: With improvements in human leukocyte antigen typing, better graft-versus-host disease prophylaxis, and other advances, can myeloablative chemotherapy conditioning replace TBI, which is more toxic?

The downstream effects of TBI can include secondary malignancies and cataracts, as well as impaired growth and impaired gonadal and cognitive function.

But the answer to that question is no, or at least, not yet.

The phase 3 trial included individuals with ALL who were aged 4-21 years at time of transplant. They were randomly assigned to receive either fractionated TBI at 12 Gy plus etoposide or chemotherapy based on a myeloablative regimen: fludarabine, thiotepa, and either busulfan or treosulfan.

The trial was stopped after 413 patients had undergone randomization – quite a bit short of the 1,000-patient goal. The trial was terminated because TBI proved clearly superior on an interim analysis at a median follow-up of 2.1 years.

The results showed that 72% of the TBI group – but only 51% of the chemotherapy arm – were relapse free at 2 years with no graft-versus-host disease (P = .0003).

The 2-year treatment-related mortality rate was 2% in the TBI group but 9% with chemotherapy conditioning (P = .03).

The study was published Feb. 1, 2020, in the Journal of Clinical Oncology.

“We recommend TBI plus etoposide conditioning for patients [aged over] 4 years old with high-risk ALL undergoing allogeneic HSCT [hematopoietic stem cell transplant],” they concluded. The investigators were led by Christina Peters, MD, a pediatrics professor at the St. Anna Children’s Cancer Research Institute, Vienna.

The benefits of TBI held on multivariate analysis and across subgroups, including children in their first and second remissions and among those with high-risk cytogenetics. Relapse risk factors, such as age at transplant, leukemic phenotype, and molecular aberrations, did not significantly affect outcomes, the authors reported.

Given that relapses plateaued with TBI at 2.5 years but were still on the upswing for patients who underwent chemoconditioning, “it is unlikely that secondary malignancies after TBI could jeopardize the survival advantage,” they wrote.

“So does this mean that the HCT community is forever chained to TBI as a standard of care? Certainly, it means that without very sound rationale to deviate, a TBI-based preparative regimen is the preferred therapy at present,” Michael Pulsipher, MD, head of blood and marrow transplantation at Children’s Hospital Los Angeles, commented in an accompanying editorial.

However, “there are approaches under study currently that may define patients who do not need TBI for high rates of cure,” he suggested. Those approaches include selecting patients with the deepest remissions and using KIR-favorable haplotype to harness natural killer cell activity.

“In our new world of chimeric antigen receptor T-cells and immunotherapies, surely we can find safer paths to success,” Dr. Pulsipher wrote.

With regard to patient selection, the investigators noted that a recent review that included more than 3,000 children with ALL found no overall survival benefit with TBI versus chemoconditioning for patients in first complete remission but worse outcomes with chemoconditioning among patients in second complete remission. “A similar trend was observed in our subgroup analyses; however, our study was not powered to assess statistical significance in a sample size of 413 patients,” they wrote.

Minimal residual disease did not influence survival outcomes, probably because the investigators were aggressive in inducing deep remission in their patients before transplant, so for most patients, MRD was undetectable or very low beforehand.

The study was funded by Amgen, Jazz Pharmaceuticals, Neovii, Medac, and others. Dr. Peters and coauthors, as well as Dr. Pulsipher have disclosed numerous ties with those and/or other companies.

A version of this article first appeared on Medscape.com.

Allogeneic hematopoietic stem-cell transplantation (AHSCT) improved disease-free survival (DFS), compared with pediatric-inspired Berlin-Frankfurt-Münster (BFM-95) chemotherapy in adults with acute lymphoblastic leukemia (ALL), according to the results of retrospective study published in Clinical Lymphoma, Myeloma & Leukemia. However, overall survival (OS) was not significantly different between the two groups, as reported by Elifcan Aladag, MD, of the Hacettepe University Faculty of Medicine, Ankara, Turkey, and colleagues.

VashiDonsk/Wikimedia Commons/Creative Commons 3.0

Despite this, “AHSCT is recommended for all patients with suitable donors, but the risk of transplant-related mortality should be kept in mind,” according to the researchers.

The multicenter study compared two different treatment approaches (BFM-95 chemotherapy regimen and AHSCT). The BFM-95 chemotherapy group comprised 47 newly diagnosed ALL patients. The transplant cohort comprised 83 patients with ALL in first complete remission who received AHSCT from fully matched human leukocyte antigen (HLA)-identical siblings. Thirty-five of the AHSCT patients (42.1%) received chemotherapy at least until the M stage of the BFM-95 protocol.

The primary endpoints of the study were OS and duration of DFS. OS was defined from the day of starting BFM-95 chemotherapy until death from any cause, and DFS was calculated from the date of complete remission until the date of first relapse or death from any cause, whichever occurred first, according to the authors.
 

Study results

The median OS was 68 months in patients who underwent AHSCT and 46 months in patients treated only with BFM-95 (P = .3). Two- and 5-year OS rates were 78% and 60% , respectively, in the AHSCT group, and 69% and 64% in the BFM-95 group (P = .06 and .13, respectively).

The median DFS was 36.6 months in patients who underwent AHSCT and 28 months in patients treated with BFM-95 (P = .033). Two- and 5-year DFS rates were 68.5% and 57%, respectively, in the AHSCT group, and 63% and 38% respectively, in the BFM-95 group (P = .12 and .029, respectively).

Mortality in the BFM-95 group was the result of sepsis due to infections (fungal infection in two patients, resistant bacterial infections in four patients). In the AHSCT group, respectively, three and seven patients died of graft-versus-host disease and bacterial infections (with fungal infections in four patients and resistant bacterial infections in three patients), according to the researchers.

“In our study, no 2-year OS and DFS difference was observed in any treatment group; however, a significant difference occurred in 5-year DFS in favor of AHSCT. This may be due to transplant-related mortality in the first 2 years, which led to no statistically significant difference,” the authors stated.

“In order to further elucidate the role of AHSCT when pediatric-derived regimens are used for the treatment of adult lymphoblastic leukemia, higher-powered randomized prospective studies are needed,” they concluded.

The authors reported that they had no conflicts of interest.

mlesney@mdedge.com

Allogeneic hematopoietic stem-cell transplantation (AHSCT) improved disease-free survival (DFS), compared with pediatric-inspired Berlin-Frankfurt-Münster (BFM-95) chemotherapy in adults with acute lymphoblastic leukemia (ALL), according to the results of retrospective study published in Clinical Lymphoma, Myeloma & Leukemia. However, overall survival (OS) was not significantly different between the two groups, as reported by Elifcan Aladag, MD, of the Hacettepe University Faculty of Medicine, Ankara, Turkey, and colleagues.

VashiDonsk/Wikimedia Commons/Creative Commons 3.0

Despite this, “AHSCT is recommended for all patients with suitable donors, but the risk of transplant-related mortality should be kept in mind,” according to the researchers.

The multicenter study compared two different treatment approaches (BFM-95 chemotherapy regimen and AHSCT). The BFM-95 chemotherapy group comprised 47 newly diagnosed ALL patients. The transplant cohort comprised 83 patients with ALL in first complete remission who received AHSCT from fully matched human leukocyte antigen (HLA)-identical siblings. Thirty-five of the AHSCT patients (42.1%) received chemotherapy at least until the M stage of the BFM-95 protocol.

The primary endpoints of the study were OS and duration of DFS. OS was defined from the day of starting BFM-95 chemotherapy until death from any cause, and DFS was calculated from the date of complete remission until the date of first relapse or death from any cause, whichever occurred first, according to the authors.
 

Study results

The median OS was 68 months in patients who underwent AHSCT and 46 months in patients treated only with BFM-95 (P = .3). Two- and 5-year OS rates were 78% and 60% , respectively, in the AHSCT group, and 69% and 64% in the BFM-95 group (P = .06 and .13, respectively).

The median DFS was 36.6 months in patients who underwent AHSCT and 28 months in patients treated with BFM-95 (P = .033). Two- and 5-year DFS rates were 68.5% and 57%, respectively, in the AHSCT group, and 63% and 38% respectively, in the BFM-95 group (P = .12 and .029, respectively).

Mortality in the BFM-95 group was the result of sepsis due to infections (fungal infection in two patients, resistant bacterial infections in four patients). In the AHSCT group, respectively, three and seven patients died of graft-versus-host disease and bacterial infections (with fungal infections in four patients and resistant bacterial infections in three patients), according to the researchers.

“In our study, no 2-year OS and DFS difference was observed in any treatment group; however, a significant difference occurred in 5-year DFS in favor of AHSCT. This may be due to transplant-related mortality in the first 2 years, which led to no statistically significant difference,” the authors stated.

“In order to further elucidate the role of AHSCT when pediatric-derived regimens are used for the treatment of adult lymphoblastic leukemia, higher-powered randomized prospective studies are needed,” they concluded.

The authors reported that they had no conflicts of interest.

mlesney@mdedge.com

Allogeneic hematopoietic stem-cell transplantation (AHSCT) improved disease-free survival (DFS), compared with pediatric-inspired Berlin-Frankfurt-Münster (BFM-95) chemotherapy in adults with acute lymphoblastic leukemia (ALL), according to the results of retrospective study published in Clinical Lymphoma, Myeloma & Leukemia. However, overall survival (OS) was not significantly different between the two groups, as reported by Elifcan Aladag, MD, of the Hacettepe University Faculty of Medicine, Ankara, Turkey, and colleagues.

VashiDonsk/Wikimedia Commons/Creative Commons 3.0

Despite this, “AHSCT is recommended for all patients with suitable donors, but the risk of transplant-related mortality should be kept in mind,” according to the researchers.

The multicenter study compared two different treatment approaches (BFM-95 chemotherapy regimen and AHSCT). The BFM-95 chemotherapy group comprised 47 newly diagnosed ALL patients. The transplant cohort comprised 83 patients with ALL in first complete remission who received AHSCT from fully matched human leukocyte antigen (HLA)-identical siblings. Thirty-five of the AHSCT patients (42.1%) received chemotherapy at least until the M stage of the BFM-95 protocol.

The primary endpoints of the study were OS and duration of DFS. OS was defined from the day of starting BFM-95 chemotherapy until death from any cause, and DFS was calculated from the date of complete remission until the date of first relapse or death from any cause, whichever occurred first, according to the authors.
 

Study results

The median OS was 68 months in patients who underwent AHSCT and 46 months in patients treated only with BFM-95 (P = .3). Two- and 5-year OS rates were 78% and 60% , respectively, in the AHSCT group, and 69% and 64% in the BFM-95 group (P = .06 and .13, respectively).

The median DFS was 36.6 months in patients who underwent AHSCT and 28 months in patients treated with BFM-95 (P = .033). Two- and 5-year DFS rates were 68.5% and 57%, respectively, in the AHSCT group, and 63% and 38% respectively, in the BFM-95 group (P = .12 and .029, respectively).

Mortality in the BFM-95 group was the result of sepsis due to infections (fungal infection in two patients, resistant bacterial infections in four patients). In the AHSCT group, respectively, three and seven patients died of graft-versus-host disease and bacterial infections (with fungal infections in four patients and resistant bacterial infections in three patients), according to the researchers.

“In our study, no 2-year OS and DFS difference was observed in any treatment group; however, a significant difference occurred in 5-year DFS in favor of AHSCT. This may be due to transplant-related mortality in the first 2 years, which led to no statistically significant difference,” the authors stated.

“In order to further elucidate the role of AHSCT when pediatric-derived regimens are used for the treatment of adult lymphoblastic leukemia, higher-powered randomized prospective studies are needed,” they concluded.

The authors reported that they had no conflicts of interest.

mlesney@mdedge.com

Blinatumomab was superior to high-risk consolidation (HC) 3 chemotherapy in a phase 3 clinical trial among children with high-risk first-relapse acute lymphoblastic leukemia (ALL), according to Franco Locatelli, MD, PhD, Ospedale Pediatrico Bambino Gesú and Sapienza, Rome.

Blinatumomab constitutes a new standard of care because of superior event-free survival (EFS) and other comparative benefits, including fewer and less severe toxicities, he said in a presentation at theannual meeting of the American Society of Hematology, which was held virtually.

About 15% of children with B-cell precursor (BCP) ALL relapse after standard treatment. Prognosis depends largely on time from diagnosis to relapse and the site of relapse. After relapse, when a second morphological complete remission (M1 marrow) is achieved, most are candidates for allogeneic hematopoietic stem cell transplant (alloHSCT), Dr. Locatelli noted. Immuno-oncotherapy with blinatumomab, a bispecific T-cell–engager molecule, has been shown to be efficacious in children with relapsed/refractory BCP-ALL.

In the open-label, controlled trial, investigators randomized children with M1 (<5% blasts) or M2 (<25% and 5% or greater blasts) marrow 1:1 after induction therapy and cycles of HC1 and HC2 chemotherapy to a third consolidation course with blinatumomab (15 µg/m²/day for 4 weeks) or HC3 (dexamethasone, vincristine, daunorubicin, methotrexate, ifosfamide, PEG-asparaginase); intrathecal chemotherapy (methotrexate/cytarabine/prednisolone) was administered before treatment. Patients achieving a second complete morphological remission (M1 marrow) after blinatumomab or HC3 proceeded to alloHSCT. EFS was the primary endpoint (from randomization until relapse date or M2 marrow after a complete response [CR], failure to achieve CR at end of treatment, second malignancy, or death from any cause).

Investigators had enrolled 108 (54 received HC3; 54 received blinatumomab) out of a target of about 202 patients when the data-monitoring committee recommended termination because of blinatumomab benefit observed at the first interim analysis. Median age was around 5.5 years (1-17), with the mean time from first diagnosis to relapse at approximately 22 months.

Dr. Locatelli reported events for 18/54 (33.3%) in the blinatumomab arm and 31/54 (57.4%) in the HC3 arm, with a median EFS of “not reached” and 7.4 months, respectively. The risk of relapse with blinatumomab was reduced by 64% versus HC3 (hazard ratio, 0.36; 95% confidence interval, 0.19-0.66, P < .001). Overall survival (OS) favored blinatumomab over HC3, as well, with a hazard ratio of 0.43 (95% CI, 0.18-1.01). Minimal residual disease (MRD) remission (MRD < 10-4) was seen in 43/46 (93.5%) blinatumomab-randomized and 25/46 (54.3%) HC3-randomized patients.

Relapses occurred more often in the HC3 group (blinatumomab 13, 24%; HC3 29, 54%) overall, and at each of the assessments at 6 months, 12 months, and 24 months. Also, MRD remissions by PCR (polymerase chain reaction) were superior in the blinatumomab arm overall (90% versus 54%) and according to baseline MRD status with strikingly divergent rates in those with MRD greater than or equal to 104 at baseline (93% blinatumomab/24% HC3). Rates were relatively similar in patients with MRD less than 104 at baseline (85% blinatumomab/87% HC3).

Grade 3 or greater treatment-emergent adverse events were reported by 30/53 (57%) and 41/51 (80%) patients in the blinatumomab and HC3 groups, respectively, with several markedly lower in the blinatumomab group (neutropenia/neutrophil count decrease 17 versus 31; anemia 15 versus 41; febrile neutropenia 4 versus 26). As expected, grade 3 or greater neurologic events occurred more frequently with blinatumomab than with HC3 (48% versus 29%); no grade 3 or greater cytokine release syndrome events were reported.

Tallying the blinatumomab benefits (superior EFS and MRD negativity prior to alloHSCT, improved OS, fewer relapses, fewer and less severe toxicities), Dr. Locatelli concluded, “Blinatumomab constitutes a new standard of care in children with high-risk first-relapse ALL.”

In the postpresentation discussion, Dr. Locatelli underscored the blinatumomab benefit versus a third course of chemotherapy: “Monotherapy with blinatumomab was able to present a higher proportion of patients in CR2 who could proceed to transplant.”

Dr. Locatelli disclosed relationships with multiple companies.

SOURCE: Locatelli F et al. ASH 2020, Abstract 268.

Blinatumomab was superior to high-risk consolidation (HC) 3 chemotherapy in a phase 3 clinical trial among children with high-risk first-relapse acute lymphoblastic leukemia (ALL), according to Franco Locatelli, MD, PhD, Ospedale Pediatrico Bambino Gesú and Sapienza, Rome.

Blinatumomab constitutes a new standard of care because of superior event-free survival (EFS) and other comparative benefits, including fewer and less severe toxicities, he said in a presentation at theannual meeting of the American Society of Hematology, which was held virtually.

About 15% of children with B-cell precursor (BCP) ALL relapse after standard treatment. Prognosis depends largely on time from diagnosis to relapse and the site of relapse. After relapse, when a second morphological complete remission (M1 marrow) is achieved, most are candidates for allogeneic hematopoietic stem cell transplant (alloHSCT), Dr. Locatelli noted. Immuno-oncotherapy with blinatumomab, a bispecific T-cell–engager molecule, has been shown to be efficacious in children with relapsed/refractory BCP-ALL.

In the open-label, controlled trial, investigators randomized children with M1 (<5% blasts) or M2 (<25% and 5% or greater blasts) marrow 1:1 after induction therapy and cycles of HC1 and HC2 chemotherapy to a third consolidation course with blinatumomab (15 µg/m²/day for 4 weeks) or HC3 (dexamethasone, vincristine, daunorubicin, methotrexate, ifosfamide, PEG-asparaginase); intrathecal chemotherapy (methotrexate/cytarabine/prednisolone) was administered before treatment. Patients achieving a second complete morphological remission (M1 marrow) after blinatumomab or HC3 proceeded to alloHSCT. EFS was the primary endpoint (from randomization until relapse date or M2 marrow after a complete response [CR], failure to achieve CR at end of treatment, second malignancy, or death from any cause).

Investigators had enrolled 108 (54 received HC3; 54 received blinatumomab) out of a target of about 202 patients when the data-monitoring committee recommended termination because of blinatumomab benefit observed at the first interim analysis. Median age was around 5.5 years (1-17), with the mean time from first diagnosis to relapse at approximately 22 months.

Dr. Locatelli reported events for 18/54 (33.3%) in the blinatumomab arm and 31/54 (57.4%) in the HC3 arm, with a median EFS of “not reached” and 7.4 months, respectively. The risk of relapse with blinatumomab was reduced by 64% versus HC3 (hazard ratio, 0.36; 95% confidence interval, 0.19-0.66, P < .001). Overall survival (OS) favored blinatumomab over HC3, as well, with a hazard ratio of 0.43 (95% CI, 0.18-1.01). Minimal residual disease (MRD) remission (MRD < 10-4) was seen in 43/46 (93.5%) blinatumomab-randomized and 25/46 (54.3%) HC3-randomized patients.

Relapses occurred more often in the HC3 group (blinatumomab 13, 24%; HC3 29, 54%) overall, and at each of the assessments at 6 months, 12 months, and 24 months. Also, MRD remissions by PCR (polymerase chain reaction) were superior in the blinatumomab arm overall (90% versus 54%) and according to baseline MRD status with strikingly divergent rates in those with MRD greater than or equal to 104 at baseline (93% blinatumomab/24% HC3). Rates were relatively similar in patients with MRD less than 104 at baseline (85% blinatumomab/87% HC3).

Grade 3 or greater treatment-emergent adverse events were reported by 30/53 (57%) and 41/51 (80%) patients in the blinatumomab and HC3 groups, respectively, with several markedly lower in the blinatumomab group (neutropenia/neutrophil count decrease 17 versus 31; anemia 15 versus 41; febrile neutropenia 4 versus 26). As expected, grade 3 or greater neurologic events occurred more frequently with blinatumomab than with HC3 (48% versus 29%); no grade 3 or greater cytokine release syndrome events were reported.

Tallying the blinatumomab benefits (superior EFS and MRD negativity prior to alloHSCT, improved OS, fewer relapses, fewer and less severe toxicities), Dr. Locatelli concluded, “Blinatumomab constitutes a new standard of care in children with high-risk first-relapse ALL.”

In the postpresentation discussion, Dr. Locatelli underscored the blinatumomab benefit versus a third course of chemotherapy: “Monotherapy with blinatumomab was able to present a higher proportion of patients in CR2 who could proceed to transplant.”

Dr. Locatelli disclosed relationships with multiple companies.

SOURCE: Locatelli F et al. ASH 2020, Abstract 268.

Blinatumomab was superior to high-risk consolidation (HC) 3 chemotherapy in a phase 3 clinical trial among children with high-risk first-relapse acute lymphoblastic leukemia (ALL), according to Franco Locatelli, MD, PhD, Ospedale Pediatrico Bambino Gesú and Sapienza, Rome.

Blinatumomab constitutes a new standard of care because of superior event-free survival (EFS) and other comparative benefits, including fewer and less severe toxicities, he said in a presentation at theannual meeting of the American Society of Hematology, which was held virtually.

About 15% of children with B-cell precursor (BCP) ALL relapse after standard treatment. Prognosis depends largely on time from diagnosis to relapse and the site of relapse. After relapse, when a second morphological complete remission (M1 marrow) is achieved, most are candidates for allogeneic hematopoietic stem cell transplant (alloHSCT), Dr. Locatelli noted. Immuno-oncotherapy with blinatumomab, a bispecific T-cell–engager molecule, has been shown to be efficacious in children with relapsed/refractory BCP-ALL.

In the open-label, controlled trial, investigators randomized children with M1 (<5% blasts) or M2 (<25% and 5% or greater blasts) marrow 1:1 after induction therapy and cycles of HC1 and HC2 chemotherapy to a third consolidation course with blinatumomab (15 µg/m²/day for 4 weeks) or HC3 (dexamethasone, vincristine, daunorubicin, methotrexate, ifosfamide, PEG-asparaginase); intrathecal chemotherapy (methotrexate/cytarabine/prednisolone) was administered before treatment. Patients achieving a second complete morphological remission (M1 marrow) after blinatumomab or HC3 proceeded to alloHSCT. EFS was the primary endpoint (from randomization until relapse date or M2 marrow after a complete response [CR], failure to achieve CR at end of treatment, second malignancy, or death from any cause).

Investigators had enrolled 108 (54 received HC3; 54 received blinatumomab) out of a target of about 202 patients when the data-monitoring committee recommended termination because of blinatumomab benefit observed at the first interim analysis. Median age was around 5.5 years (1-17), with the mean time from first diagnosis to relapse at approximately 22 months.

Dr. Locatelli reported events for 18/54 (33.3%) in the blinatumomab arm and 31/54 (57.4%) in the HC3 arm, with a median EFS of “not reached” and 7.4 months, respectively. The risk of relapse with blinatumomab was reduced by 64% versus HC3 (hazard ratio, 0.36; 95% confidence interval, 0.19-0.66, P < .001). Overall survival (OS) favored blinatumomab over HC3, as well, with a hazard ratio of 0.43 (95% CI, 0.18-1.01). Minimal residual disease (MRD) remission (MRD < 10-4) was seen in 43/46 (93.5%) blinatumomab-randomized and 25/46 (54.3%) HC3-randomized patients.

Relapses occurred more often in the HC3 group (blinatumomab 13, 24%; HC3 29, 54%) overall, and at each of the assessments at 6 months, 12 months, and 24 months. Also, MRD remissions by PCR (polymerase chain reaction) were superior in the blinatumomab arm overall (90% versus 54%) and according to baseline MRD status with strikingly divergent rates in those with MRD greater than or equal to 104 at baseline (93% blinatumomab/24% HC3). Rates were relatively similar in patients with MRD less than 104 at baseline (85% blinatumomab/87% HC3).

Grade 3 or greater treatment-emergent adverse events were reported by 30/53 (57%) and 41/51 (80%) patients in the blinatumomab and HC3 groups, respectively, with several markedly lower in the blinatumomab group (neutropenia/neutrophil count decrease 17 versus 31; anemia 15 versus 41; febrile neutropenia 4 versus 26). As expected, grade 3 or greater neurologic events occurred more frequently with blinatumomab than with HC3 (48% versus 29%); no grade 3 or greater cytokine release syndrome events were reported.

Tallying the blinatumomab benefits (superior EFS and MRD negativity prior to alloHSCT, improved OS, fewer relapses, fewer and less severe toxicities), Dr. Locatelli concluded, “Blinatumomab constitutes a new standard of care in children with high-risk first-relapse ALL.”

In the postpresentation discussion, Dr. Locatelli underscored the blinatumomab benefit versus a third course of chemotherapy: “Monotherapy with blinatumomab was able to present a higher proportion of patients in CR2 who could proceed to transplant.”

Dr. Locatelli disclosed relationships with multiple companies.

SOURCE: Locatelli F et al. ASH 2020, Abstract 268.

In heavily pretreated pediatric patients with relapsed or refractory acute lymphoblastic leukemia (ALL) or lymphoblastic lymphoma (LL), venetoclax plus navitoclax with chemotherapy was well tolerated with promising responses, according to results of a phase 1 trial. Delayed count recovery, however, stated lead author Jeffrey E. Rubnitz, MD, PhD, St. Jude’s Children’s Research Hospital, Memphis, remained a key safety concern.
 

Unmet medical need

Despite intensive chemotherapy and novel therapeutics, Dr. Rubnitz said in a virtual oral presentation at the annual meeting of the American Society of Hematology, patients with relapsed or refractory ALL and LL have a poor prognosis and represent an unmet medical need. Venetoclax, a potent, highly selective oral B-cell lymphoma 2 inhibitor, and navitoclax, an oral BCL-2, BCL-XL, and BCL-W inhibitor, directly bind their BCL-2 family member targets to promote apoptosis. In ALL preclinical models, venetoclax and navitoclax have demonstrated antileukemic effects, which suggests dependence on BCL-2 family members. Venetoclax efficacy associated with BCL-2 family inhibition may be potentiated and dose-limiting thrombocytopenia associated with standard-dose navitoclax monotherapy may be avoided by adding venetoclax to low-dose navitoclax. Previous reports of an ongoing phase 1, multicenter, open-label, dose-escalation study in an adult and pediatric population (NCT03181126), Dr. Rubnitz noted, showed the venetoclax/navitoclax/chemotherapy combination to be well tolerated with promising response rates. In the current report, Dr. Rubnitz presented data on the safety, tolerability, pharmacokinetics, and antitumor activity of the triplet regimen in the subgroup of pediatric patients.

The study included pediatric patients (ages, 4-18 years and weight ≥20 kg) receiving venetoclax (weight-adjusted equivalent of 400 mg daily) and navitoclax at three dose levels (25, 50, 100 mg) for patients weighing ≥45 kg and two dose levels (25, 50 mg) for patients weighing <45 kg. At investigator’s discretion, patients could receive chemotherapy (polyethylene glycosylated–asparaginase, vincristine, and dexamethasone). The primary outcomes were safety (including incidence of dose-limiting toxicities and adverse events) and pharmacokinetics. A safety expansion cohort assessed a 21-day dosing schedule of venetoclax at 400 mg followed by 7 days off plus navitoclax at 50 mg (patients ≥45 kg) or 25 mg (patients <45 kg).

Investigators enrolled 18 patients <18 years (median age, 10 years; range, 6-16; 56% male), with 12 in the dose-escalation cohort and 6 in the safety-expansion cohort. Three patients had prior chimeric antigen receptor (CAR) T treatment and four had received prior stem cell transplantation. In the overall cohort, B-cell ALL was most common (n = 13, 72%), with T-cell ALL (n = 3, 17%) and LL (n = 2, 11%) following. The median number of prior therapies was 2 (range 1-6). All patients received chemotherapy.
 

Grade 3-4 adverse events

Venetoclax-related grade 3-4 adverse events occurred in 56% of patients. Similarly, navitoclax-related grade 3-4 events were reported in 56% of patients. Navitoclax dose-limiting toxicities occurred in two patients (11%), delayed count recovery on 25 mg and sepsis on 50 mg. No grade 5 adverse events and tumor lysis syndrome were reported.

Among secondary endpoint efficacy parameters, complete responses, CRs with incomplete marrow recovery (CRi) and CRs without platelet recovery (CRp) combined occurred in 62% of B-ALL patients (8/13), 33% of T-cell ALL patients (1/3) and in 50% of LL patients (1/2). Separately, CRs/CRis/CRps occurred in 33%/22%/0% of all patients, respectively.

Subsequently, 5 of 18 (28%) of patients proceeded to stem cell transplantation and 3 (17%) to CAR T. Eight patients (44%) died from disease progression.
 

BH3 profiling

BH3 profiling revealed that at baseline, patients with B-cell ALL had more diversity in BCL-2 and BCL-XL dependency than did patients with T-cell ALL or early T-cell precursor ALL. The fact that responses were observed in patients who were BCL-2 or BCL-XL dependent, Dr. Rubnitz said, supports the use of venetoclax plus navitoclax in these patients. Analysis of these results led to a recommended phase 2 dose for pediatric patients of 400 mg venetoclax with 25 mg navitoclax (for patients weighing <45 kg) or 50 mg navitoclax (for patients weighing 45 kg or more).

Dr. Rubnitz concluded: “Venetoclax plus navitoclax plus chemotherapy was well tolerated in pediatric patients with relapsed/refractory ALL or LL, with promising response rates observed in a heavily pretreated pediatric population.”

Asked whether the combination might be used also before the refractory setting, in a minimal residual disease (MRD) setting, Dr. Rubnitz replied: “We have a lot of safety data on venetoclax but very little on navitoclax. The next trial, being developed by Seth Karol, MD, will include relapsed patients. MRD-positive patients will also be eligible for enrollment.” To a further question as to whether guiding titration via BH3 profiling would lead to improved outcomes, Dr. Rubnitz said, “I think BH3 profiling can be used to identify which patients will respond to these drugs, but we are still a long way from using it for titrating the doses and dose ratios for the two drugs.”

Dr. Rubnitz disclosed research funding from AbbVie.

SOURCE: Rubnitz JE et al. ASH 2020, Abstract 466.

In heavily pretreated pediatric patients with relapsed or refractory acute lymphoblastic leukemia (ALL) or lymphoblastic lymphoma (LL), venetoclax plus navitoclax with chemotherapy was well tolerated with promising responses, according to results of a phase 1 trial. Delayed count recovery, however, stated lead author Jeffrey E. Rubnitz, MD, PhD, St. Jude’s Children’s Research Hospital, Memphis, remained a key safety concern.
 

Unmet medical need

Despite intensive chemotherapy and novel therapeutics, Dr. Rubnitz said in a virtual oral presentation at the annual meeting of the American Society of Hematology, patients with relapsed or refractory ALL and LL have a poor prognosis and represent an unmet medical need. Venetoclax, a potent, highly selective oral B-cell lymphoma 2 inhibitor, and navitoclax, an oral BCL-2, BCL-XL, and BCL-W inhibitor, directly bind their BCL-2 family member targets to promote apoptosis. In ALL preclinical models, venetoclax and navitoclax have demonstrated antileukemic effects, which suggests dependence on BCL-2 family members. Venetoclax efficacy associated with BCL-2 family inhibition may be potentiated and dose-limiting thrombocytopenia associated with standard-dose navitoclax monotherapy may be avoided by adding venetoclax to low-dose navitoclax. Previous reports of an ongoing phase 1, multicenter, open-label, dose-escalation study in an adult and pediatric population (NCT03181126), Dr. Rubnitz noted, showed the venetoclax/navitoclax/chemotherapy combination to be well tolerated with promising response rates. In the current report, Dr. Rubnitz presented data on the safety, tolerability, pharmacokinetics, and antitumor activity of the triplet regimen in the subgroup of pediatric patients.

The study included pediatric patients (ages, 4-18 years and weight ≥20 kg) receiving venetoclax (weight-adjusted equivalent of 400 mg daily) and navitoclax at three dose levels (25, 50, 100 mg) for patients weighing ≥45 kg and two dose levels (25, 50 mg) for patients weighing <45 kg. At investigator’s discretion, patients could receive chemotherapy (polyethylene glycosylated–asparaginase, vincristine, and dexamethasone). The primary outcomes were safety (including incidence of dose-limiting toxicities and adverse events) and pharmacokinetics. A safety expansion cohort assessed a 21-day dosing schedule of venetoclax at 400 mg followed by 7 days off plus navitoclax at 50 mg (patients ≥45 kg) or 25 mg (patients <45 kg).

Investigators enrolled 18 patients <18 years (median age, 10 years; range, 6-16; 56% male), with 12 in the dose-escalation cohort and 6 in the safety-expansion cohort. Three patients had prior chimeric antigen receptor (CAR) T treatment and four had received prior stem cell transplantation. In the overall cohort, B-cell ALL was most common (n = 13, 72%), with T-cell ALL (n = 3, 17%) and LL (n = 2, 11%) following. The median number of prior therapies was 2 (range 1-6). All patients received chemotherapy.
 

Grade 3-4 adverse events

Venetoclax-related grade 3-4 adverse events occurred in 56% of patients. Similarly, navitoclax-related grade 3-4 events were reported in 56% of patients. Navitoclax dose-limiting toxicities occurred in two patients (11%), delayed count recovery on 25 mg and sepsis on 50 mg. No grade 5 adverse events and tumor lysis syndrome were reported.

Among secondary endpoint efficacy parameters, complete responses, CRs with incomplete marrow recovery (CRi) and CRs without platelet recovery (CRp) combined occurred in 62% of B-ALL patients (8/13), 33% of T-cell ALL patients (1/3) and in 50% of LL patients (1/2). Separately, CRs/CRis/CRps occurred in 33%/22%/0% of all patients, respectively.

Subsequently, 5 of 18 (28%) of patients proceeded to stem cell transplantation and 3 (17%) to CAR T. Eight patients (44%) died from disease progression.
 

BH3 profiling

BH3 profiling revealed that at baseline, patients with B-cell ALL had more diversity in BCL-2 and BCL-XL dependency than did patients with T-cell ALL or early T-cell precursor ALL. The fact that responses were observed in patients who were BCL-2 or BCL-XL dependent, Dr. Rubnitz said, supports the use of venetoclax plus navitoclax in these patients. Analysis of these results led to a recommended phase 2 dose for pediatric patients of 400 mg venetoclax with 25 mg navitoclax (for patients weighing <45 kg) or 50 mg navitoclax (for patients weighing 45 kg or more).

Dr. Rubnitz concluded: “Venetoclax plus navitoclax plus chemotherapy was well tolerated in pediatric patients with relapsed/refractory ALL or LL, with promising response rates observed in a heavily pretreated pediatric population.”

Asked whether the combination might be used also before the refractory setting, in a minimal residual disease (MRD) setting, Dr. Rubnitz replied: “We have a lot of safety data on venetoclax but very little on navitoclax. The next trial, being developed by Seth Karol, MD, will include relapsed patients. MRD-positive patients will also be eligible for enrollment.” To a further question as to whether guiding titration via BH3 profiling would lead to improved outcomes, Dr. Rubnitz said, “I think BH3 profiling can be used to identify which patients will respond to these drugs, but we are still a long way from using it for titrating the doses and dose ratios for the two drugs.”

Dr. Rubnitz disclosed research funding from AbbVie.

SOURCE: Rubnitz JE et al. ASH 2020, Abstract 466.

In heavily pretreated pediatric patients with relapsed or refractory acute lymphoblastic leukemia (ALL) or lymphoblastic lymphoma (LL), venetoclax plus navitoclax with chemotherapy was well tolerated with promising responses, according to results of a phase 1 trial. Delayed count recovery, however, stated lead author Jeffrey E. Rubnitz, MD, PhD, St. Jude’s Children’s Research Hospital, Memphis, remained a key safety concern.
 

Unmet medical need

Despite intensive chemotherapy and novel therapeutics, Dr. Rubnitz said in a virtual oral presentation at the annual meeting of the American Society of Hematology, patients with relapsed or refractory ALL and LL have a poor prognosis and represent an unmet medical need. Venetoclax, a potent, highly selective oral B-cell lymphoma 2 inhibitor, and navitoclax, an oral BCL-2, BCL-XL, and BCL-W inhibitor, directly bind their BCL-2 family member targets to promote apoptosis. In ALL preclinical models, venetoclax and navitoclax have demonstrated antileukemic effects, which suggests dependence on BCL-2 family members. Venetoclax efficacy associated with BCL-2 family inhibition may be potentiated and dose-limiting thrombocytopenia associated with standard-dose navitoclax monotherapy may be avoided by adding venetoclax to low-dose navitoclax. Previous reports of an ongoing phase 1, multicenter, open-label, dose-escalation study in an adult and pediatric population (NCT03181126), Dr. Rubnitz noted, showed the venetoclax/navitoclax/chemotherapy combination to be well tolerated with promising response rates. In the current report, Dr. Rubnitz presented data on the safety, tolerability, pharmacokinetics, and antitumor activity of the triplet regimen in the subgroup of pediatric patients.

The study included pediatric patients (ages, 4-18 years and weight ≥20 kg) receiving venetoclax (weight-adjusted equivalent of 400 mg daily) and navitoclax at three dose levels (25, 50, 100 mg) for patients weighing ≥45 kg and two dose levels (25, 50 mg) for patients weighing <45 kg. At investigator’s discretion, patients could receive chemotherapy (polyethylene glycosylated–asparaginase, vincristine, and dexamethasone). The primary outcomes were safety (including incidence of dose-limiting toxicities and adverse events) and pharmacokinetics. A safety expansion cohort assessed a 21-day dosing schedule of venetoclax at 400 mg followed by 7 days off plus navitoclax at 50 mg (patients ≥45 kg) or 25 mg (patients <45 kg).

Investigators enrolled 18 patients <18 years (median age, 10 years; range, 6-16; 56% male), with 12 in the dose-escalation cohort and 6 in the safety-expansion cohort. Three patients had prior chimeric antigen receptor (CAR) T treatment and four had received prior stem cell transplantation. In the overall cohort, B-cell ALL was most common (n = 13, 72%), with T-cell ALL (n = 3, 17%) and LL (n = 2, 11%) following. The median number of prior therapies was 2 (range 1-6). All patients received chemotherapy.
 

Grade 3-4 adverse events

Venetoclax-related grade 3-4 adverse events occurred in 56% of patients. Similarly, navitoclax-related grade 3-4 events were reported in 56% of patients. Navitoclax dose-limiting toxicities occurred in two patients (11%), delayed count recovery on 25 mg and sepsis on 50 mg. No grade 5 adverse events and tumor lysis syndrome were reported.

Among secondary endpoint efficacy parameters, complete responses, CRs with incomplete marrow recovery (CRi) and CRs without platelet recovery (CRp) combined occurred in 62% of B-ALL patients (8/13), 33% of T-cell ALL patients (1/3) and in 50% of LL patients (1/2). Separately, CRs/CRis/CRps occurred in 33%/22%/0% of all patients, respectively.

Subsequently, 5 of 18 (28%) of patients proceeded to stem cell transplantation and 3 (17%) to CAR T. Eight patients (44%) died from disease progression.
 

BH3 profiling

BH3 profiling revealed that at baseline, patients with B-cell ALL had more diversity in BCL-2 and BCL-XL dependency than did patients with T-cell ALL or early T-cell precursor ALL. The fact that responses were observed in patients who were BCL-2 or BCL-XL dependent, Dr. Rubnitz said, supports the use of venetoclax plus navitoclax in these patients. Analysis of these results led to a recommended phase 2 dose for pediatric patients of 400 mg venetoclax with 25 mg navitoclax (for patients weighing <45 kg) or 50 mg navitoclax (for patients weighing 45 kg or more).

Dr. Rubnitz concluded: “Venetoclax plus navitoclax plus chemotherapy was well tolerated in pediatric patients with relapsed/refractory ALL or LL, with promising response rates observed in a heavily pretreated pediatric population.”

Asked whether the combination might be used also before the refractory setting, in a minimal residual disease (MRD) setting, Dr. Rubnitz replied: “We have a lot of safety data on venetoclax but very little on navitoclax. The next trial, being developed by Seth Karol, MD, will include relapsed patients. MRD-positive patients will also be eligible for enrollment.” To a further question as to whether guiding titration via BH3 profiling would lead to improved outcomes, Dr. Rubnitz said, “I think BH3 profiling can be used to identify which patients will respond to these drugs, but we are still a long way from using it for titrating the doses and dose ratios for the two drugs.”

Dr. Rubnitz disclosed research funding from AbbVie.

SOURCE: Rubnitz JE et al. ASH 2020, Abstract 466.

Hyper-CVAD (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone) with sequential blinatumomab is highly effective as frontline therapy for Philadelphia Chromosome (Ph)–negative B-cell acute lymphoblastic leukemia (ALL), according to results of a phase 2 study reported at the annual meeting of the American Society of Hematology.

Favorable minimal residual disease (MRD) negativity and overall survival with low higher-grade toxicities suggest that reductions in chemotherapy in this setting are feasible, said Nicholas J. Short, MD, of the University of Texas MD Anderson Cancer Center, Houston.

While complete response rates with current ALL therapy are 80%-90%, long-term overall survival is only 40%-50%. Blinatumomab, a bispecific T-cell–engaging CD3-CD19 antibody, has been shown to be superior to chemotherapy in relapsed/refractory B-cell ALL, and to produce high rates of MRD eradication, the most important prognostic factor in ALL, Dr. Short said at the meeting, which was held virtually.

The hypothesis of the current study was that early incorporation of blinatumomab with hyper-CVAD in patients with newly diagnosed Ph-negative B-cell ALL would decrease the need for intensive chemotherapy and lead to higher efficacy and cure rates with less myelosuppression. Patients were required to have a performance status of 3 or less, total bilirubin 2 mg/dL or less and creatinine 2 mg/dL or less. Investigators enrolled 38 patients (mean age, 37 years,; range, 17-59) with most (79%) in performance status 0-1. The primary endpoint was relapse-free survival (RFS).
 

Study details

Patients received hyper-CVAD alternating with high-dose methotrexate and cytarabine for up to four cycles followed by four cycles of blinatumomab at standard doses. Those with CD20-positive disease (1% or greater percentage of the cells) received eight doses of ofatumumab or rituximab, and prophylactic intrathecal chemotherapy was given eight times in the first four cycles. Maintenance consisted of alternating blocks of POMP (6-mercaptopurine, vincristine, methotrexate, prednisone) and blinatumomab. When two patients with high-risk features experienced early relapse, investigators amended the protocol to allow blinatumomab after only two cycles of hyper-CVAD in those with high-risk features (e.g., CRLF2 positive by flow cytometry, complex karyotype, KMT2A rearranged, low hypodiploidy/near triploidy, TP53 mutation, or persistent MRD). Nineteen patients (56%) had at least one high-risk feature, and 82% received ofatumumab or rituximab. Six patients were in complete remission at the start of the study (four of them MRD negative).

Complete responses

After induction, complete responses were achieved in 81% (26/32), with all patients achieving a complete response at some point, according to Dr. Short. The MRD negativity rate was 71% (24/34) after induction and 97% (33/34) at any time. Among the 38 patients, all with complete response at median follow-up of 24 months (range, 2-45), relapses occurred only in those 5 patients with high-risk features. Twelve patients underwent transplant in the first remission. Two relapsed, both with high-risk features. The other 21 patients had ongoing complete responses.

RFS at 1- and 2-years was 80% and 71%, respectively. Five among seven relapses were without hematopoietic stem cell transplantation, and 2 were post HSCT. Two deaths occurred in patients with complete responses (one pulmonary embolism and one with post-HSCT complications). Overall survival at 1 and 2 years was 85% and 80%, respectively, with the 2-year rate comparable with prior reports for hyper-CVAD plus ofatumumab, Dr. Short said.

The most common nonhematologic grade 3-4 adverse events with hyper-CVAD plus blinatumomab were ALT/AST elevation (24%) and hyperglycemia (21%). The overall cytokine release syndrome rate was 13%, with 3% for higher-grade reactions. The rate for blinatumomab-related neurologic events was 45% overall and 13% for higher grades, with 1 discontinuation attributed to grade 2 encephalopathy and dysphasia.

“Overall, this study shows the potential benefit of incorporating frontline blinatumomab into the treatment of younger adults with newly diagnosed Philadelphia chromosome–negative B-cell lymphoma, and shows, as well, that reduction of chemotherapy in this context is feasible,” Dr. Short stated.

“Ultimately, often for any patients with acute leukemias and ALL, our only chance to cure them is in the frontline setting, so our approach is to include all of the most effective agents we have. So that means including blinatumomab in all of our frontline regimens in clinical trials – and now we’ve amended that to add inotuzumab ozogamicin with the goal of deepening responses and increasing cure rates,” he added.

Dr. Short reported consulting with Takeda Oncology and Astrazeneca, and receiving research funding and honoraria from Amgen, Astella, and Takeda Oncology.

SOURCE: Short NG et al. ASH 2020, Abstract 464.

Hyper-CVAD (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone) with sequential blinatumomab is highly effective as frontline therapy for Philadelphia Chromosome (Ph)–negative B-cell acute lymphoblastic leukemia (ALL), according to results of a phase 2 study reported at the annual meeting of the American Society of Hematology.

Favorable minimal residual disease (MRD) negativity and overall survival with low higher-grade toxicities suggest that reductions in chemotherapy in this setting are feasible, said Nicholas J. Short, MD, of the University of Texas MD Anderson Cancer Center, Houston.

While complete response rates with current ALL therapy are 80%-90%, long-term overall survival is only 40%-50%. Blinatumomab, a bispecific T-cell–engaging CD3-CD19 antibody, has been shown to be superior to chemotherapy in relapsed/refractory B-cell ALL, and to produce high rates of MRD eradication, the most important prognostic factor in ALL, Dr. Short said at the meeting, which was held virtually.

The hypothesis of the current study was that early incorporation of blinatumomab with hyper-CVAD in patients with newly diagnosed Ph-negative B-cell ALL would decrease the need for intensive chemotherapy and lead to higher efficacy and cure rates with less myelosuppression. Patients were required to have a performance status of 3 or less, total bilirubin 2 mg/dL or less and creatinine 2 mg/dL or less. Investigators enrolled 38 patients (mean age, 37 years,; range, 17-59) with most (79%) in performance status 0-1. The primary endpoint was relapse-free survival (RFS).
 

Study details

Patients received hyper-CVAD alternating with high-dose methotrexate and cytarabine for up to four cycles followed by four cycles of blinatumomab at standard doses. Those with CD20-positive disease (1% or greater percentage of the cells) received eight doses of ofatumumab or rituximab, and prophylactic intrathecal chemotherapy was given eight times in the first four cycles. Maintenance consisted of alternating blocks of POMP (6-mercaptopurine, vincristine, methotrexate, prednisone) and blinatumomab. When two patients with high-risk features experienced early relapse, investigators amended the protocol to allow blinatumomab after only two cycles of hyper-CVAD in those with high-risk features (e.g., CRLF2 positive by flow cytometry, complex karyotype, KMT2A rearranged, low hypodiploidy/near triploidy, TP53 mutation, or persistent MRD). Nineteen patients (56%) had at least one high-risk feature, and 82% received ofatumumab or rituximab. Six patients were in complete remission at the start of the study (four of them MRD negative).

Complete responses

After induction, complete responses were achieved in 81% (26/32), with all patients achieving a complete response at some point, according to Dr. Short. The MRD negativity rate was 71% (24/34) after induction and 97% (33/34) at any time. Among the 38 patients, all with complete response at median follow-up of 24 months (range, 2-45), relapses occurred only in those 5 patients with high-risk features. Twelve patients underwent transplant in the first remission. Two relapsed, both with high-risk features. The other 21 patients had ongoing complete responses.

RFS at 1- and 2-years was 80% and 71%, respectively. Five among seven relapses were without hematopoietic stem cell transplantation, and 2 were post HSCT. Two deaths occurred in patients with complete responses (one pulmonary embolism and one with post-HSCT complications). Overall survival at 1 and 2 years was 85% and 80%, respectively, with the 2-year rate comparable with prior reports for hyper-CVAD plus ofatumumab, Dr. Short said.

The most common nonhematologic grade 3-4 adverse events with hyper-CVAD plus blinatumomab were ALT/AST elevation (24%) and hyperglycemia (21%). The overall cytokine release syndrome rate was 13%, with 3% for higher-grade reactions. The rate for blinatumomab-related neurologic events was 45% overall and 13% for higher grades, with 1 discontinuation attributed to grade 2 encephalopathy and dysphasia.

“Overall, this study shows the potential benefit of incorporating frontline blinatumomab into the treatment of younger adults with newly diagnosed Philadelphia chromosome–negative B-cell lymphoma, and shows, as well, that reduction of chemotherapy in this context is feasible,” Dr. Short stated.

“Ultimately, often for any patients with acute leukemias and ALL, our only chance to cure them is in the frontline setting, so our approach is to include all of the most effective agents we have. So that means including blinatumomab in all of our frontline regimens in clinical trials – and now we’ve amended that to add inotuzumab ozogamicin with the goal of deepening responses and increasing cure rates,” he added.

Dr. Short reported consulting with Takeda Oncology and Astrazeneca, and receiving research funding and honoraria from Amgen, Astella, and Takeda Oncology.

SOURCE: Short NG et al. ASH 2020, Abstract 464.

Hyper-CVAD (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone) with sequential blinatumomab is highly effective as frontline therapy for Philadelphia Chromosome (Ph)–negative B-cell acute lymphoblastic leukemia (ALL), according to results of a phase 2 study reported at the annual meeting of the American Society of Hematology.

Favorable minimal residual disease (MRD) negativity and overall survival with low higher-grade toxicities suggest that reductions in chemotherapy in this setting are feasible, said Nicholas J. Short, MD, of the University of Texas MD Anderson Cancer Center, Houston.

While complete response rates with current ALL therapy are 80%-90%, long-term overall survival is only 40%-50%. Blinatumomab, a bispecific T-cell–engaging CD3-CD19 antibody, has been shown to be superior to chemotherapy in relapsed/refractory B-cell ALL, and to produce high rates of MRD eradication, the most important prognostic factor in ALL, Dr. Short said at the meeting, which was held virtually.

The hypothesis of the current study was that early incorporation of blinatumomab with hyper-CVAD in patients with newly diagnosed Ph-negative B-cell ALL would decrease the need for intensive chemotherapy and lead to higher efficacy and cure rates with less myelosuppression. Patients were required to have a performance status of 3 or less, total bilirubin 2 mg/dL or less and creatinine 2 mg/dL or less. Investigators enrolled 38 patients (mean age, 37 years,; range, 17-59) with most (79%) in performance status 0-1. The primary endpoint was relapse-free survival (RFS).
 

Study details

Patients received hyper-CVAD alternating with high-dose methotrexate and cytarabine for up to four cycles followed by four cycles of blinatumomab at standard doses. Those with CD20-positive disease (1% or greater percentage of the cells) received eight doses of ofatumumab or rituximab, and prophylactic intrathecal chemotherapy was given eight times in the first four cycles. Maintenance consisted of alternating blocks of POMP (6-mercaptopurine, vincristine, methotrexate, prednisone) and blinatumomab. When two patients with high-risk features experienced early relapse, investigators amended the protocol to allow blinatumomab after only two cycles of hyper-CVAD in those with high-risk features (e.g., CRLF2 positive by flow cytometry, complex karyotype, KMT2A rearranged, low hypodiploidy/near triploidy, TP53 mutation, or persistent MRD). Nineteen patients (56%) had at least one high-risk feature, and 82% received ofatumumab or rituximab. Six patients were in complete remission at the start of the study (four of them MRD negative).

Complete responses

After induction, complete responses were achieved in 81% (26/32), with all patients achieving a complete response at some point, according to Dr. Short. The MRD negativity rate was 71% (24/34) after induction and 97% (33/34) at any time. Among the 38 patients, all with complete response at median follow-up of 24 months (range, 2-45), relapses occurred only in those 5 patients with high-risk features. Twelve patients underwent transplant in the first remission. Two relapsed, both with high-risk features. The other 21 patients had ongoing complete responses.

RFS at 1- and 2-years was 80% and 71%, respectively. Five among seven relapses were without hematopoietic stem cell transplantation, and 2 were post HSCT. Two deaths occurred in patients with complete responses (one pulmonary embolism and one with post-HSCT complications). Overall survival at 1 and 2 years was 85% and 80%, respectively, with the 2-year rate comparable with prior reports for hyper-CVAD plus ofatumumab, Dr. Short said.

The most common nonhematologic grade 3-4 adverse events with hyper-CVAD plus blinatumomab were ALT/AST elevation (24%) and hyperglycemia (21%). The overall cytokine release syndrome rate was 13%, with 3% for higher-grade reactions. The rate for blinatumomab-related neurologic events was 45% overall and 13% for higher grades, with 1 discontinuation attributed to grade 2 encephalopathy and dysphasia.

“Overall, this study shows the potential benefit of incorporating frontline blinatumomab into the treatment of younger adults with newly diagnosed Philadelphia chromosome–negative B-cell lymphoma, and shows, as well, that reduction of chemotherapy in this context is feasible,” Dr. Short stated.

“Ultimately, often for any patients with acute leukemias and ALL, our only chance to cure them is in the frontline setting, so our approach is to include all of the most effective agents we have. So that means including blinatumomab in all of our frontline regimens in clinical trials – and now we’ve amended that to add inotuzumab ozogamicin with the goal of deepening responses and increasing cure rates,” he added.

Dr. Short reported consulting with Takeda Oncology and Astrazeneca, and receiving research funding and honoraria from Amgen, Astella, and Takeda Oncology.

SOURCE: Short NG et al. ASH 2020, Abstract 464.

Patients with hematologic disease who develop COVID-19 may experience substantial morbidity and mortality related to SARS-CoV-2 infection, according to recent registry data reported at the all-virtual annual meeting of the American Society of Hematology.

Overall mortality was 28% for the first 250 patients entered into the ASH Research Collaborative COVID-19 Registry for Hematology, researchers reported in an abstract of their study findings.

However, the burden of death and moderate-to-severe COVID-19 outcomes was highest in patients with poorer prognosis and those with relapsed/refractory hematological disease, they added.

The most commonly represented malignancies were acute leukemia, non-Hodgkin lymphoma, and myeloma or amyloidosis, according to the report.

Taken together, the findings do support an “emerging consensus” that COVID-19 related morbidity and mortality is significant in these patients, authors said – however, the current findings may not be reason enough to support a change in treatment course for the underlying disease.

“We see no reason, based on our data, to withhold intensive therapies from patients with underlying hematologic malignancies and favorable prognoses, if aggressive supportive care is consistent with patient preferences,” wrote the researchers.

ASH President Stephanie Lee, MD, MPH, said these registry findings are important to better understand how SARS-CoV-2 is affecting not only patients with hematologic diseases, but also individuals who experience COVID-19-related hematologic complications.

However, the findings are limited due to the heterogeneity of diseases, symptoms, and treatments represented in the registry, said Dr. Lee, associate director of the clinical research division at Fred Hutchinson Cancer Center in Seattle.

“More data will be coming in, but I think this is an example of trying to harness real-world information to try to learn things until we get more controlled studies,” Dr. Lee said in a media briefing held in advance of the ASH meeting.
 

Comorbidities and more

Patients with blood cancers are often older and may have comorbidities such as diabetes or hypertension that have been linked to poor COVID-19 outcomes, according to the authors of the report, led by William A. Wood, MD, MPH, associate professor of medicine with the UNC Lineberger Comprehensive Cancer Center in Chapel Hill, N.C.

Moreover, these patients may have underlying immune dysfunction and may receive chemotherapy or immunotherapy that is “profoundly immunosuppressive,” Dr. Wood and coauthors said in their report.

To date, however, risks of morbidity and mortality related to SARS-CoV-2 infection have not been well defined in this patient population, authors said.

More data is emerging now from the ASH Research Collaborative COVID-19 Registry for Hematology, which includes data on patients positive for COVID-19 who have a past or present hematologic condition or have experienced a hematologic complication related to COVID-19.

All data from the registry is being made available through a dashboard on the ASH Research Collaborative website, which as of Dec. 1, 2020, included 693 complete cases.

The data cut in the ASH abstract includes the first 250 patients enrolled at 74 sites around the world, the authors said. The most common malignancies included acute leukemia in 33%, non-Hodgkin lymphoma in 27%, and myeloma or amyloidosis in 16%.

The most frequently reported symptoms included fever in 73%, cough in 67%, dyspnea in 50%, and fatigue in 40%, according to that report.

At the time of this data snapshot, treatment with COVID-19-directed therapies including hydroxychloroquine or azithromycin were common, reported in 76 and 59 patients, respectively, in the cohort.

Batch submissions from sites with high incidence of COVID-19 infection are ongoing. The registry has been expanded to include nonmalignant hematologic diseases, and the registry will continue to accumulate data as a resource for the hematology community.

Overall mortality was 28% at the time, according to the abstract, with nearly all of the deaths occurring in patients classified as having COVID-19 that was moderate (i.e., requiring hospitalization) or severe (i.e., requiring ICU admission).

“In some instances, death occurred after a decision was made to forgo ICU admission in favor of a palliative approach,” said Dr. Wood and coauthors in their report.

Dr. Wood reported research funding from Pfizer, consultancy with Teladoc/Best Doctors, and honoraria from the ASH Research Collaborative. Coauthors provided disclosures related to Celgene, Madrigal Pharmaceuticals, Pharmacyclics, and Amgen, among others.

SOURCE: Wood WA et al. ASH 2020, Abstract 215.

Patients with hematologic disease who develop COVID-19 may experience substantial morbidity and mortality related to SARS-CoV-2 infection, according to recent registry data reported at the all-virtual annual meeting of the American Society of Hematology.

Overall mortality was 28% for the first 250 patients entered into the ASH Research Collaborative COVID-19 Registry for Hematology, researchers reported in an abstract of their study findings.

However, the burden of death and moderate-to-severe COVID-19 outcomes was highest in patients with poorer prognosis and those with relapsed/refractory hematological disease, they added.

The most commonly represented malignancies were acute leukemia, non-Hodgkin lymphoma, and myeloma or amyloidosis, according to the report.

Taken together, the findings do support an “emerging consensus” that COVID-19 related morbidity and mortality is significant in these patients, authors said – however, the current findings may not be reason enough to support a change in treatment course for the underlying disease.

“We see no reason, based on our data, to withhold intensive therapies from patients with underlying hematologic malignancies and favorable prognoses, if aggressive supportive care is consistent with patient preferences,” wrote the researchers.

ASH President Stephanie Lee, MD, MPH, said these registry findings are important to better understand how SARS-CoV-2 is affecting not only patients with hematologic diseases, but also individuals who experience COVID-19-related hematologic complications.

However, the findings are limited due to the heterogeneity of diseases, symptoms, and treatments represented in the registry, said Dr. Lee, associate director of the clinical research division at Fred Hutchinson Cancer Center in Seattle.

“More data will be coming in, but I think this is an example of trying to harness real-world information to try to learn things until we get more controlled studies,” Dr. Lee said in a media briefing held in advance of the ASH meeting.
 

Comorbidities and more

Patients with blood cancers are often older and may have comorbidities such as diabetes or hypertension that have been linked to poor COVID-19 outcomes, according to the authors of the report, led by William A. Wood, MD, MPH, associate professor of medicine with the UNC Lineberger Comprehensive Cancer Center in Chapel Hill, N.C.

Moreover, these patients may have underlying immune dysfunction and may receive chemotherapy or immunotherapy that is “profoundly immunosuppressive,” Dr. Wood and coauthors said in their report.

To date, however, risks of morbidity and mortality related to SARS-CoV-2 infection have not been well defined in this patient population, authors said.

More data is emerging now from the ASH Research Collaborative COVID-19 Registry for Hematology, which includes data on patients positive for COVID-19 who have a past or present hematologic condition or have experienced a hematologic complication related to COVID-19.

All data from the registry is being made available through a dashboard on the ASH Research Collaborative website, which as of Dec. 1, 2020, included 693 complete cases.

The data cut in the ASH abstract includes the first 250 patients enrolled at 74 sites around the world, the authors said. The most common malignancies included acute leukemia in 33%, non-Hodgkin lymphoma in 27%, and myeloma or amyloidosis in 16%.

The most frequently reported symptoms included fever in 73%, cough in 67%, dyspnea in 50%, and fatigue in 40%, according to that report.

At the time of this data snapshot, treatment with COVID-19-directed therapies including hydroxychloroquine or azithromycin were common, reported in 76 and 59 patients, respectively, in the cohort.

Batch submissions from sites with high incidence of COVID-19 infection are ongoing. The registry has been expanded to include nonmalignant hematologic diseases, and the registry will continue to accumulate data as a resource for the hematology community.

Overall mortality was 28% at the time, according to the abstract, with nearly all of the deaths occurring in patients classified as having COVID-19 that was moderate (i.e., requiring hospitalization) or severe (i.e., requiring ICU admission).

“In some instances, death occurred after a decision was made to forgo ICU admission in favor of a palliative approach,” said Dr. Wood and coauthors in their report.

Dr. Wood reported research funding from Pfizer, consultancy with Teladoc/Best Doctors, and honoraria from the ASH Research Collaborative. Coauthors provided disclosures related to Celgene, Madrigal Pharmaceuticals, Pharmacyclics, and Amgen, among others.

SOURCE: Wood WA et al. ASH 2020, Abstract 215.

Patients with hematologic disease who develop COVID-19 may experience substantial morbidity and mortality related to SARS-CoV-2 infection, according to recent registry data reported at the all-virtual annual meeting of the American Society of Hematology.

Overall mortality was 28% for the first 250 patients entered into the ASH Research Collaborative COVID-19 Registry for Hematology, researchers reported in an abstract of their study findings.

However, the burden of death and moderate-to-severe COVID-19 outcomes was highest in patients with poorer prognosis and those with relapsed/refractory hematological disease, they added.

The most commonly represented malignancies were acute leukemia, non-Hodgkin lymphoma, and myeloma or amyloidosis, according to the report.

Taken together, the findings do support an “emerging consensus” that COVID-19 related morbidity and mortality is significant in these patients, authors said – however, the current findings may not be reason enough to support a change in treatment course for the underlying disease.

“We see no reason, based on our data, to withhold intensive therapies from patients with underlying hematologic malignancies and favorable prognoses, if aggressive supportive care is consistent with patient preferences,” wrote the researchers.

ASH President Stephanie Lee, MD, MPH, said these registry findings are important to better understand how SARS-CoV-2 is affecting not only patients with hematologic diseases, but also individuals who experience COVID-19-related hematologic complications.

However, the findings are limited due to the heterogeneity of diseases, symptoms, and treatments represented in the registry, said Dr. Lee, associate director of the clinical research division at Fred Hutchinson Cancer Center in Seattle.

“More data will be coming in, but I think this is an example of trying to harness real-world information to try to learn things until we get more controlled studies,” Dr. Lee said in a media briefing held in advance of the ASH meeting.
 

Comorbidities and more

Patients with blood cancers are often older and may have comorbidities such as diabetes or hypertension that have been linked to poor COVID-19 outcomes, according to the authors of the report, led by William A. Wood, MD, MPH, associate professor of medicine with the UNC Lineberger Comprehensive Cancer Center in Chapel Hill, N.C.

Moreover, these patients may have underlying immune dysfunction and may receive chemotherapy or immunotherapy that is “profoundly immunosuppressive,” Dr. Wood and coauthors said in their report.

To date, however, risks of morbidity and mortality related to SARS-CoV-2 infection have not been well defined in this patient population, authors said.

More data is emerging now from the ASH Research Collaborative COVID-19 Registry for Hematology, which includes data on patients positive for COVID-19 who have a past or present hematologic condition or have experienced a hematologic complication related to COVID-19.

All data from the registry is being made available through a dashboard on the ASH Research Collaborative website, which as of Dec. 1, 2020, included 693 complete cases.

The data cut in the ASH abstract includes the first 250 patients enrolled at 74 sites around the world, the authors said. The most common malignancies included acute leukemia in 33%, non-Hodgkin lymphoma in 27%, and myeloma or amyloidosis in 16%.

The most frequently reported symptoms included fever in 73%, cough in 67%, dyspnea in 50%, and fatigue in 40%, according to that report.

At the time of this data snapshot, treatment with COVID-19-directed therapies including hydroxychloroquine or azithromycin were common, reported in 76 and 59 patients, respectively, in the cohort.

Batch submissions from sites with high incidence of COVID-19 infection are ongoing. The registry has been expanded to include nonmalignant hematologic diseases, and the registry will continue to accumulate data as a resource for the hematology community.

Overall mortality was 28% at the time, according to the abstract, with nearly all of the deaths occurring in patients classified as having COVID-19 that was moderate (i.e., requiring hospitalization) or severe (i.e., requiring ICU admission).

“In some instances, death occurred after a decision was made to forgo ICU admission in favor of a palliative approach,” said Dr. Wood and coauthors in their report.

Dr. Wood reported research funding from Pfizer, consultancy with Teladoc/Best Doctors, and honoraria from the ASH Research Collaborative. Coauthors provided disclosures related to Celgene, Madrigal Pharmaceuticals, Pharmacyclics, and Amgen, among others.

SOURCE: Wood WA et al. ASH 2020, Abstract 215.