TBD Meeting (2893-23)

Long-acting antiretroviral therapy (ART) for HIV involving injections every 1 or 2 months not only shows noninferiority to a standard daily oral treatment regimen, it also suppresses HIV even in patients who do not already have virologic suppression, as is typically required before initiation, results from two new studies suggest.

Meanwhile, a third study shows early promise of a long-acting ART regimen that could require injections only twice yearly.

“Instead of having the burden of taking a pill every day, patients with HIV can now have these choices of being able to forget about their treatment for up to 2 months at a time,” Moti N. Ramgopal, MD, first author of one of the three studies, said in a press conference at the Conference on Retroviruses and Opportunistic Infections. “My patients tell me that it’s game-changing for them.”
 

First head-to-head comparison

The injectable intramuscular combination of cabotegravir and rilpivirine, administered once every 1 or 2 months, is the first and only long-acting ART to be approved by the Food and Drug Administration for people with HIV. At the meeting, Dr. Ramgopal, from the Midway Immunology and Research Center in Fort Pierce, Fla., reported the results from the first head-to-head study comparing the regimen with the standard daily oral regimen of bictegravir/emtricitabine/tenofovir alafenamide (B/FTC/TAF).

For the phase 3b SOLAR trial, adults with HIV who were already virologically suppressed and treated with daily B/FTC/TAF were randomly assigned to remain on the oral regimen (n = 223) or switch to the long-acting injections every 2 months, either with an oral lead-in (n = 173) or without a lead-in (n = 274).

The results after 12 months showed noninferiority between the groups, with 90% of the long-acting ART group and 93% in the oral daily pill group maintaining viral suppression, defined as plasma HIV-1 RNA less than 50 copies/mL.

Two patients (0.4%) receiving the long-acting ART in a modified-intention to treat and 3 (0.6%) in the intention-to-treat populations had confirmed virologic failure, and rates of adverse events leading to withdrawal were 6% with the long-acting ART group versus 1% with the oral treatment group.

As many as 90% of subjects reported preferring the long-acting ART over their previous oral therapy at the end of the study, and those in the long-acting group also reported significantly greater improvements in quality of life on the HIV Treatment Satisfaction Questionnaire status version compared with the oral therapy group at the end of the study (P < .001).

Prior to the randomization, as many as 47% of patients on the oral regimen reported “always” or “often” having psychosocial challenges with the daily therapy, including worries of having their HIV status revealed and forgetting to take the medication.

“These data demonstrate that [the long-acting regimen] addresses important unmet needs for people with HIV who are virally suppressed on oral daily HIV therapy, while improving the quality of life,” said Dr. Ramgopal.
 

Suppression at onset not necessarily required

For all of its benefits, a key caveat of the cabotegravir and rilpivirine long-acting regimen is that it is approved only for patients who have already achieved viral suppression and are currently on oral ART, meaning some of the people most in need, including those with unstable housing, mental illness, or substance abuse disorders, may be excluded.

To evaluate the therapy’s efficacy among those patient types, Monica Gandhi, MD, MPH, professor of medicine and associate division chief at the University of California, San Francisco, enrolled 133 participants between June 2021 and November 2022 at the Ward 86 HIV Clinic, a safety-net clinic in San Francisco, to initiate long-acting ART. Participants included 57 patients (43%) with untreated or unsuppressed HIV, and 76 who were virally suppressed on oral ART.

Of the whole study group, 66% reported unstable housing, 8% reported experiencing homelessness, 38% reported having a mental illness, and 33% reported substance use.

Although all of the subjects (100%) who started with viral suppression remained suppressed over the study’s 26-week follow-up, the rate of viral suppression at the study’s end was nearly as high – 55 of 57 subjects (96.5%) – among those who started long-acting ART without having viral suppression.

Of note, the overall rate of study participants who did not achieve or maintain viral suppression (1.5%) was consistent with rates reported in clinical trials of long-acting ART in people with HIV who had previously achieved viral suppression on daily oral ART.

“Our patient population does not look like the patient population that got enrolled in the clinical trials to determine the approval criteria for long-acting ART,” Dr. Gandhi said in presenting the findings.

“If 10% of the population carries 90% of the HIV virus – which we see in modeling – then we need innovations for this population if we want to end the HIV epidemic,” she added.

“We tried long-acting ART in our diverse, urban, low-income population and we saw very high virologic suppression rates equal to those that were seen in the clinical trials,” Dr. Ghandi reported. “This shows that long-acting ART, used creatively and used boldly, could really make a dent in the [efforts] to end the HIV epidemic movement.”

Commenting on the study in a press statement, Nora Volkow, MD, director of the National Institute on Drug Abuse, said “Dr. Gandhi and her team have made state-of-the-art HIV treatment finally available to people with unique challenges, like those who use drugs, and have found success.”

“This is the sweet spot for addressing HIV – thinking outside the box to deliver care in a way that meets people’s needs, even when that means it happens outside the clinic walls, by phone, or on neighborhood streets,” she said. “This can be done, but it requires creativity and resolve.”
 

Twice-yearly dosing option?

Looking ahead, an even more intriguing scenario of a long-acting ART requiring injections only once every 6 months may be getting closer to fruition. Researchers at CROI 2023 reported early but promising safety and efficacy results of an innovative combination of the first-in-class HIV-1 capsid inhibitor lenacapavir with teropavimab and zinlirvimab, two broadly neutralizing antibodies (bNAbs).

To achieve the goal of the longer-acting therapy, Joseph J. Eron, MD, of the University of North Carolina at Chapel Hill, and colleagues modified both antibodies to extend their half-lives and allow less-frequent dosing.

For the phase 1b trial, 20 adult patients with virologically suppressed HIV for at least 18 months were randomly assigned to one of two doses of the ART, both groups receiving lenacapavir at 927 mg subcutaneous after oral loading, plus teropavimab (30 mg/kg IV) and zinlirvimab at either 10 mg/kg or 30 mg/kg.

Patients had to have a CD4 count greater than 500 and CD4 nadir greater than 350, and importantly, patients had to demonstrate sensitivity on DNA phenotyping to both bNAbs at baseline.

After 26 weeks, 18 of the 20 participants (90%) maintained a viral suppression of HIV-1 RNA less than 50 copies/mL.

Of the remaining two patients, one in the 10–mg/kg zinlirvimab group had a confirmed HIV RNA of 50 c/mL (155 copies/mL, confirmed 524 copies/mL) at week 16 and was able to be resuppressed with reinitiation of baseline ART, and one participant in the zinlirvimab 30 mg/kg group withdrew consent at week 12, with viral suppression, and chose to go back on oral therapy

The safety profile looked favorable, with no serious adverse events and two patients with grade 3 AEs, including one experiencing an injection site cellulitis and one with injection site erythema.

Dr. Eron noted that “bNAb sensitivity is an important issue and a limitation for broad use, [because] only about 50% of people with HIV in the U.S. would be sensitive to both antibodies.”

However, “we are doing a pilot of only 10 participants looking to see if it works with sensitivity to a single antibody, which would increase [applicability] to about 90% of people with HIV,” he said in an interview.

At a press conference, Dr. Eron commented on how far HIV treatment has come, from the early days of patients having to wake up every 4 hours to take their medication, then to having to take 15-20 pills a day, to the current option of long-acting ART every other month, and now the potential of just a twice-yearly treatment.

“This is a very preliminary proof-of-concept study and not a very large study, but I think it’s incredibly important,” he said.

The SOLAR study was funded by ViiV Healthcare. Dr. Ramgopal has received speaking and/or consulting fees from AbbVie, Gilead Sciences, Janssen, Merck, and ViiV Healthcare. Dr. Eron’s study was funded by Gilead Sciences.

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

Long-acting antiretroviral therapy (ART) for HIV involving injections every 1 or 2 months not only shows noninferiority to a standard daily oral treatment regimen, it also suppresses HIV even in patients who do not already have virologic suppression, as is typically required before initiation, results from two new studies suggest.

Meanwhile, a third study shows early promise of a long-acting ART regimen that could require injections only twice yearly.

“Instead of having the burden of taking a pill every day, patients with HIV can now have these choices of being able to forget about their treatment for up to 2 months at a time,” Moti N. Ramgopal, MD, first author of one of the three studies, said in a press conference at the Conference on Retroviruses and Opportunistic Infections. “My patients tell me that it’s game-changing for them.”
 

First head-to-head comparison

The injectable intramuscular combination of cabotegravir and rilpivirine, administered once every 1 or 2 months, is the first and only long-acting ART to be approved by the Food and Drug Administration for people with HIV. At the meeting, Dr. Ramgopal, from the Midway Immunology and Research Center in Fort Pierce, Fla., reported the results from the first head-to-head study comparing the regimen with the standard daily oral regimen of bictegravir/emtricitabine/tenofovir alafenamide (B/FTC/TAF).

For the phase 3b SOLAR trial, adults with HIV who were already virologically suppressed and treated with daily B/FTC/TAF were randomly assigned to remain on the oral regimen (n = 223) or switch to the long-acting injections every 2 months, either with an oral lead-in (n = 173) or without a lead-in (n = 274).

The results after 12 months showed noninferiority between the groups, with 90% of the long-acting ART group and 93% in the oral daily pill group maintaining viral suppression, defined as plasma HIV-1 RNA less than 50 copies/mL.

Two patients (0.4%) receiving the long-acting ART in a modified-intention to treat and 3 (0.6%) in the intention-to-treat populations had confirmed virologic failure, and rates of adverse events leading to withdrawal were 6% with the long-acting ART group versus 1% with the oral treatment group.

As many as 90% of subjects reported preferring the long-acting ART over their previous oral therapy at the end of the study, and those in the long-acting group also reported significantly greater improvements in quality of life on the HIV Treatment Satisfaction Questionnaire status version compared with the oral therapy group at the end of the study (P < .001).

Prior to the randomization, as many as 47% of patients on the oral regimen reported “always” or “often” having psychosocial challenges with the daily therapy, including worries of having their HIV status revealed and forgetting to take the medication.

“These data demonstrate that [the long-acting regimen] addresses important unmet needs for people with HIV who are virally suppressed on oral daily HIV therapy, while improving the quality of life,” said Dr. Ramgopal.
 

Suppression at onset not necessarily required

For all of its benefits, a key caveat of the cabotegravir and rilpivirine long-acting regimen is that it is approved only for patients who have already achieved viral suppression and are currently on oral ART, meaning some of the people most in need, including those with unstable housing, mental illness, or substance abuse disorders, may be excluded.

To evaluate the therapy’s efficacy among those patient types, Monica Gandhi, MD, MPH, professor of medicine and associate division chief at the University of California, San Francisco, enrolled 133 participants between June 2021 and November 2022 at the Ward 86 HIV Clinic, a safety-net clinic in San Francisco, to initiate long-acting ART. Participants included 57 patients (43%) with untreated or unsuppressed HIV, and 76 who were virally suppressed on oral ART.

Of the whole study group, 66% reported unstable housing, 8% reported experiencing homelessness, 38% reported having a mental illness, and 33% reported substance use.

Although all of the subjects (100%) who started with viral suppression remained suppressed over the study’s 26-week follow-up, the rate of viral suppression at the study’s end was nearly as high – 55 of 57 subjects (96.5%) – among those who started long-acting ART without having viral suppression.

Of note, the overall rate of study participants who did not achieve or maintain viral suppression (1.5%) was consistent with rates reported in clinical trials of long-acting ART in people with HIV who had previously achieved viral suppression on daily oral ART.

“Our patient population does not look like the patient population that got enrolled in the clinical trials to determine the approval criteria for long-acting ART,” Dr. Gandhi said in presenting the findings.

“If 10% of the population carries 90% of the HIV virus – which we see in modeling – then we need innovations for this population if we want to end the HIV epidemic,” she added.

“We tried long-acting ART in our diverse, urban, low-income population and we saw very high virologic suppression rates equal to those that were seen in the clinical trials,” Dr. Ghandi reported. “This shows that long-acting ART, used creatively and used boldly, could really make a dent in the [efforts] to end the HIV epidemic movement.”

Commenting on the study in a press statement, Nora Volkow, MD, director of the National Institute on Drug Abuse, said “Dr. Gandhi and her team have made state-of-the-art HIV treatment finally available to people with unique challenges, like those who use drugs, and have found success.”

“This is the sweet spot for addressing HIV – thinking outside the box to deliver care in a way that meets people’s needs, even when that means it happens outside the clinic walls, by phone, or on neighborhood streets,” she said. “This can be done, but it requires creativity and resolve.”
 

Twice-yearly dosing option?

Looking ahead, an even more intriguing scenario of a long-acting ART requiring injections only once every 6 months may be getting closer to fruition. Researchers at CROI 2023 reported early but promising safety and efficacy results of an innovative combination of the first-in-class HIV-1 capsid inhibitor lenacapavir with teropavimab and zinlirvimab, two broadly neutralizing antibodies (bNAbs).

To achieve the goal of the longer-acting therapy, Joseph J. Eron, MD, of the University of North Carolina at Chapel Hill, and colleagues modified both antibodies to extend their half-lives and allow less-frequent dosing.

For the phase 1b trial, 20 adult patients with virologically suppressed HIV for at least 18 months were randomly assigned to one of two doses of the ART, both groups receiving lenacapavir at 927 mg subcutaneous after oral loading, plus teropavimab (30 mg/kg IV) and zinlirvimab at either 10 mg/kg or 30 mg/kg.

Patients had to have a CD4 count greater than 500 and CD4 nadir greater than 350, and importantly, patients had to demonstrate sensitivity on DNA phenotyping to both bNAbs at baseline.

After 26 weeks, 18 of the 20 participants (90%) maintained a viral suppression of HIV-1 RNA less than 50 copies/mL.

Of the remaining two patients, one in the 10–mg/kg zinlirvimab group had a confirmed HIV RNA of 50 c/mL (155 copies/mL, confirmed 524 copies/mL) at week 16 and was able to be resuppressed with reinitiation of baseline ART, and one participant in the zinlirvimab 30 mg/kg group withdrew consent at week 12, with viral suppression, and chose to go back on oral therapy

The safety profile looked favorable, with no serious adverse events and two patients with grade 3 AEs, including one experiencing an injection site cellulitis and one with injection site erythema.

Dr. Eron noted that “bNAb sensitivity is an important issue and a limitation for broad use, [because] only about 50% of people with HIV in the U.S. would be sensitive to both antibodies.”

However, “we are doing a pilot of only 10 participants looking to see if it works with sensitivity to a single antibody, which would increase [applicability] to about 90% of people with HIV,” he said in an interview.

At a press conference, Dr. Eron commented on how far HIV treatment has come, from the early days of patients having to wake up every 4 hours to take their medication, then to having to take 15-20 pills a day, to the current option of long-acting ART every other month, and now the potential of just a twice-yearly treatment.

“This is a very preliminary proof-of-concept study and not a very large study, but I think it’s incredibly important,” he said.

The SOLAR study was funded by ViiV Healthcare. Dr. Ramgopal has received speaking and/or consulting fees from AbbVie, Gilead Sciences, Janssen, Merck, and ViiV Healthcare. Dr. Eron’s study was funded by Gilead Sciences.

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

Long-acting antiretroviral therapy (ART) for HIV involving injections every 1 or 2 months not only shows noninferiority to a standard daily oral treatment regimen, it also suppresses HIV even in patients who do not already have virologic suppression, as is typically required before initiation, results from two new studies suggest.

Meanwhile, a third study shows early promise of a long-acting ART regimen that could require injections only twice yearly.

“Instead of having the burden of taking a pill every day, patients with HIV can now have these choices of being able to forget about their treatment for up to 2 months at a time,” Moti N. Ramgopal, MD, first author of one of the three studies, said in a press conference at the Conference on Retroviruses and Opportunistic Infections. “My patients tell me that it’s game-changing for them.”
 

First head-to-head comparison

The injectable intramuscular combination of cabotegravir and rilpivirine, administered once every 1 or 2 months, is the first and only long-acting ART to be approved by the Food and Drug Administration for people with HIV. At the meeting, Dr. Ramgopal, from the Midway Immunology and Research Center in Fort Pierce, Fla., reported the results from the first head-to-head study comparing the regimen with the standard daily oral regimen of bictegravir/emtricitabine/tenofovir alafenamide (B/FTC/TAF).

For the phase 3b SOLAR trial, adults with HIV who were already virologically suppressed and treated with daily B/FTC/TAF were randomly assigned to remain on the oral regimen (n = 223) or switch to the long-acting injections every 2 months, either with an oral lead-in (n = 173) or without a lead-in (n = 274).

The results after 12 months showed noninferiority between the groups, with 90% of the long-acting ART group and 93% in the oral daily pill group maintaining viral suppression, defined as plasma HIV-1 RNA less than 50 copies/mL.

Two patients (0.4%) receiving the long-acting ART in a modified-intention to treat and 3 (0.6%) in the intention-to-treat populations had confirmed virologic failure, and rates of adverse events leading to withdrawal were 6% with the long-acting ART group versus 1% with the oral treatment group.

As many as 90% of subjects reported preferring the long-acting ART over their previous oral therapy at the end of the study, and those in the long-acting group also reported significantly greater improvements in quality of life on the HIV Treatment Satisfaction Questionnaire status version compared with the oral therapy group at the end of the study (P < .001).

Prior to the randomization, as many as 47% of patients on the oral regimen reported “always” or “often” having psychosocial challenges with the daily therapy, including worries of having their HIV status revealed and forgetting to take the medication.

“These data demonstrate that [the long-acting regimen] addresses important unmet needs for people with HIV who are virally suppressed on oral daily HIV therapy, while improving the quality of life,” said Dr. Ramgopal.
 

Suppression at onset not necessarily required

For all of its benefits, a key caveat of the cabotegravir and rilpivirine long-acting regimen is that it is approved only for patients who have already achieved viral suppression and are currently on oral ART, meaning some of the people most in need, including those with unstable housing, mental illness, or substance abuse disorders, may be excluded.

To evaluate the therapy’s efficacy among those patient types, Monica Gandhi, MD, MPH, professor of medicine and associate division chief at the University of California, San Francisco, enrolled 133 participants between June 2021 and November 2022 at the Ward 86 HIV Clinic, a safety-net clinic in San Francisco, to initiate long-acting ART. Participants included 57 patients (43%) with untreated or unsuppressed HIV, and 76 who were virally suppressed on oral ART.

Of the whole study group, 66% reported unstable housing, 8% reported experiencing homelessness, 38% reported having a mental illness, and 33% reported substance use.

Although all of the subjects (100%) who started with viral suppression remained suppressed over the study’s 26-week follow-up, the rate of viral suppression at the study’s end was nearly as high – 55 of 57 subjects (96.5%) – among those who started long-acting ART without having viral suppression.

Of note, the overall rate of study participants who did not achieve or maintain viral suppression (1.5%) was consistent with rates reported in clinical trials of long-acting ART in people with HIV who had previously achieved viral suppression on daily oral ART.

“Our patient population does not look like the patient population that got enrolled in the clinical trials to determine the approval criteria for long-acting ART,” Dr. Gandhi said in presenting the findings.

“If 10% of the population carries 90% of the HIV virus – which we see in modeling – then we need innovations for this population if we want to end the HIV epidemic,” she added.

“We tried long-acting ART in our diverse, urban, low-income population and we saw very high virologic suppression rates equal to those that were seen in the clinical trials,” Dr. Ghandi reported. “This shows that long-acting ART, used creatively and used boldly, could really make a dent in the [efforts] to end the HIV epidemic movement.”

Commenting on the study in a press statement, Nora Volkow, MD, director of the National Institute on Drug Abuse, said “Dr. Gandhi and her team have made state-of-the-art HIV treatment finally available to people with unique challenges, like those who use drugs, and have found success.”

“This is the sweet spot for addressing HIV – thinking outside the box to deliver care in a way that meets people’s needs, even when that means it happens outside the clinic walls, by phone, or on neighborhood streets,” she said. “This can be done, but it requires creativity and resolve.”
 

Twice-yearly dosing option?

Looking ahead, an even more intriguing scenario of a long-acting ART requiring injections only once every 6 months may be getting closer to fruition. Researchers at CROI 2023 reported early but promising safety and efficacy results of an innovative combination of the first-in-class HIV-1 capsid inhibitor lenacapavir with teropavimab and zinlirvimab, two broadly neutralizing antibodies (bNAbs).

To achieve the goal of the longer-acting therapy, Joseph J. Eron, MD, of the University of North Carolina at Chapel Hill, and colleagues modified both antibodies to extend their half-lives and allow less-frequent dosing.

For the phase 1b trial, 20 adult patients with virologically suppressed HIV for at least 18 months were randomly assigned to one of two doses of the ART, both groups receiving lenacapavir at 927 mg subcutaneous after oral loading, plus teropavimab (30 mg/kg IV) and zinlirvimab at either 10 mg/kg or 30 mg/kg.

Patients had to have a CD4 count greater than 500 and CD4 nadir greater than 350, and importantly, patients had to demonstrate sensitivity on DNA phenotyping to both bNAbs at baseline.

After 26 weeks, 18 of the 20 participants (90%) maintained a viral suppression of HIV-1 RNA less than 50 copies/mL.

Of the remaining two patients, one in the 10–mg/kg zinlirvimab group had a confirmed HIV RNA of 50 c/mL (155 copies/mL, confirmed 524 copies/mL) at week 16 and was able to be resuppressed with reinitiation of baseline ART, and one participant in the zinlirvimab 30 mg/kg group withdrew consent at week 12, with viral suppression, and chose to go back on oral therapy

The safety profile looked favorable, with no serious adverse events and two patients with grade 3 AEs, including one experiencing an injection site cellulitis and one with injection site erythema.

Dr. Eron noted that “bNAb sensitivity is an important issue and a limitation for broad use, [because] only about 50% of people with HIV in the U.S. would be sensitive to both antibodies.”

However, “we are doing a pilot of only 10 participants looking to see if it works with sensitivity to a single antibody, which would increase [applicability] to about 90% of people with HIV,” he said in an interview.

At a press conference, Dr. Eron commented on how far HIV treatment has come, from the early days of patients having to wake up every 4 hours to take their medication, then to having to take 15-20 pills a day, to the current option of long-acting ART every other month, and now the potential of just a twice-yearly treatment.

“This is a very preliminary proof-of-concept study and not a very large study, but I think it’s incredibly important,” he said.

The SOLAR study was funded by ViiV Healthcare. Dr. Ramgopal has received speaking and/or consulting fees from AbbVie, Gilead Sciences, Janssen, Merck, and ViiV Healthcare. Dr. Eron’s study was funded by Gilead Sciences.

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

The benefits of doxycycline postexposure prophylaxis (Doxy PEP) in preventing the transmission of sexually transmitted infections (STIs) in men and transgender women do not appear to extend to cisgender women, who have disproportionately high rates of infection in many regions.

“This was the first trial to evaluate doxycycline PEP for cisgender women,” said first author Jenell Stewart, DO, of the University of Minnesota, Minneapolis, in discussing the findings at a press conference at the Conference on Retroviruses & Opportunistic Infections.

“Unfortunately, our primary outcome was not statistically significant – we did not see a reduction in STIs among cisgender women, which is in stark contrast to [reported effects] among cisgender men and transgender women,” she said.

The findings are from a study of 449 nonpregnant cisgender women (mean age, 24 years) in Kenya who had been taking daily oral HIV preexposure prophylaxis (PrEP) for a median of about 7 months.

The women were randomly assigned to receive either Doxy PEP 200 mg, to be taken within 72 hours of sex (n = 224), or standard care, which included quarterly screening and treatment of STIs (n = 225).

Of the women, 36.7% reported transactional sex at enrollment; their baseline prevalence of STIs was 17.9%, including 14.1% with chlamydia, 3.8% gonorrhea, and 0.4% syphilis. There were no differences between the study groups.

In surveys, 78% of the women reported adherence to the use of Doxy PEP; they took the prophylaxis at least as many days as they had sex.

Nevertheless, there was no significant difference in the incidence of STIs, reported over 1 year, at quarterly visits that included genital STI testing, between groups, with 50 patients in the Doxy PEP group and 59 in the standard screening group developing STIs (relative risk, 0.88; P = .51).

Of the infections, 85 were chlamydia, including 35 in the Doxy PEP group and 50 with standard of care, while 31 were gonorrhea, including 19 in the Doxy PEP group and 12 with standard of care; 8 had both infections, and there was 1 syphilis infection.

The results were consistent across subanalyses of patients grouped according to STI, who became pregnant (n = 80), or sorted by other factors including age, contraceptive use, transactional sex, and STI at baseline.

None of the women developed HIV, and there were no serious events associated with the Doxy PEP treatment.
 

Cisgender women bear ‘highest burden’ of STIs

The findings are disappointing in light of the higher rates of STIs among cisgender women, with the Centers for Disease Control and Prevention reporting that women also disproportionately bear the long-term consequences of STIs.

“For example, each year, untreated sexually transmitted diseases cause infertility in at least 20,000 women in the United States, and a pregnant woman is highly likely to pass syphilis unto her unborn baby if left untested or untreated,” the CDC reports.

The STI rates are particularly high for women taking HIV PrEP in regions like East Africa, where rates of STIs among cisgender women in many cases are higher than rates for men taking PrEP in high income countries, Dr. Stewart said.

Previous studies of Doxy PEP in men and transgender women taking HIV PrEP, including new research presented at CROI, have shown highly encouraging reductions in STIs, at rates of up to approximately 80% for chlamydia and syphilis.
 

Adherence, anatomy, resistance

The key theories for the lack of a prevention of infections in cisgender women surround the issues of resistances, as well as anatomy and adherence, said Dr. Stewart.

In terms of bacterial resistances, while initial testing in a limited number of samples the study found no evidence of markers of resistance for chlamydia, all of the gonorrhea samples did show tetracycline-resistant N gonorrhea at baseline and follow-up in both groups.

Regarding anatomic differences, doxycycline may not prevent STIs in endocervical tissue among cisgender women, Dr. Stewart noted. Women are known to be at higher risk of infection because the lining of the vagina is thinner than the skin of the penis, allowing for easier penetration of bacteria and viruses.

The study was designed to optimize adherence to Doxy PEP. Measures included monitoring with weekly text message surveys, in which the women reported a high rate of adherence.

The overall retention rate in the study was high; as many as 97% of the quarterly follow-up visits were completed, including 95% in the Doxy PEP group and 98% of the standard care group. The response rate for the weekly surveys was 81%.

Of note, women reported the use of the treatment to be “imperfect,” suggesting social problems, such as biases toward the use of the prophylaxis.

The results underscore the need for ongoing efforts to make sure no groups of patients are left behind as interventions advance, Dr. Stewart said.

“The burden of STIs on cisgender women is large and growing,” she concluded. “STI prevention interventions are needed.”

Commenting on the study, Renee A. Heffron, PhD, MPH, said the findings “are somewhat surprising because results from trials in other populations have been positive.

“But cisgender women are exposed through the cervix, and this tissue is different from rectal or urethral tissue,” Dr. Heffron, a professor at the department of medicine and director of the Center for AIDS Research at the University of Alabama, Birmingham, told this news organization.

Further findings from the research should help shed light on key issues of adherence and drug concentration levels in cervical tissue, she added.

“For cisgender women, these data are the first and the beginning of understanding whether this is a viable strategy,” Dr. Heffron said.

“We have more to learn to better understand the results from the trial main outcomes, and if there are tweaks to this strategy that would improve efficacy.”

The authors and Dr. Heffron have disclosed no relevant financial relationships.

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

The benefits of doxycycline postexposure prophylaxis (Doxy PEP) in preventing the transmission of sexually transmitted infections (STIs) in men and transgender women do not appear to extend to cisgender women, who have disproportionately high rates of infection in many regions.

“This was the first trial to evaluate doxycycline PEP for cisgender women,” said first author Jenell Stewart, DO, of the University of Minnesota, Minneapolis, in discussing the findings at a press conference at the Conference on Retroviruses & Opportunistic Infections.

“Unfortunately, our primary outcome was not statistically significant – we did not see a reduction in STIs among cisgender women, which is in stark contrast to [reported effects] among cisgender men and transgender women,” she said.

The findings are from a study of 449 nonpregnant cisgender women (mean age, 24 years) in Kenya who had been taking daily oral HIV preexposure prophylaxis (PrEP) for a median of about 7 months.

The women were randomly assigned to receive either Doxy PEP 200 mg, to be taken within 72 hours of sex (n = 224), or standard care, which included quarterly screening and treatment of STIs (n = 225).

Of the women, 36.7% reported transactional sex at enrollment; their baseline prevalence of STIs was 17.9%, including 14.1% with chlamydia, 3.8% gonorrhea, and 0.4% syphilis. There were no differences between the study groups.

In surveys, 78% of the women reported adherence to the use of Doxy PEP; they took the prophylaxis at least as many days as they had sex.

Nevertheless, there was no significant difference in the incidence of STIs, reported over 1 year, at quarterly visits that included genital STI testing, between groups, with 50 patients in the Doxy PEP group and 59 in the standard screening group developing STIs (relative risk, 0.88; P = .51).

Of the infections, 85 were chlamydia, including 35 in the Doxy PEP group and 50 with standard of care, while 31 were gonorrhea, including 19 in the Doxy PEP group and 12 with standard of care; 8 had both infections, and there was 1 syphilis infection.

The results were consistent across subanalyses of patients grouped according to STI, who became pregnant (n = 80), or sorted by other factors including age, contraceptive use, transactional sex, and STI at baseline.

None of the women developed HIV, and there were no serious events associated with the Doxy PEP treatment.
 

Cisgender women bear ‘highest burden’ of STIs

The findings are disappointing in light of the higher rates of STIs among cisgender women, with the Centers for Disease Control and Prevention reporting that women also disproportionately bear the long-term consequences of STIs.

“For example, each year, untreated sexually transmitted diseases cause infertility in at least 20,000 women in the United States, and a pregnant woman is highly likely to pass syphilis unto her unborn baby if left untested or untreated,” the CDC reports.

The STI rates are particularly high for women taking HIV PrEP in regions like East Africa, where rates of STIs among cisgender women in many cases are higher than rates for men taking PrEP in high income countries, Dr. Stewart said.

Previous studies of Doxy PEP in men and transgender women taking HIV PrEP, including new research presented at CROI, have shown highly encouraging reductions in STIs, at rates of up to approximately 80% for chlamydia and syphilis.
 

Adherence, anatomy, resistance

The key theories for the lack of a prevention of infections in cisgender women surround the issues of resistances, as well as anatomy and adherence, said Dr. Stewart.

In terms of bacterial resistances, while initial testing in a limited number of samples the study found no evidence of markers of resistance for chlamydia, all of the gonorrhea samples did show tetracycline-resistant N gonorrhea at baseline and follow-up in both groups.

Regarding anatomic differences, doxycycline may not prevent STIs in endocervical tissue among cisgender women, Dr. Stewart noted. Women are known to be at higher risk of infection because the lining of the vagina is thinner than the skin of the penis, allowing for easier penetration of bacteria and viruses.

The study was designed to optimize adherence to Doxy PEP. Measures included monitoring with weekly text message surveys, in which the women reported a high rate of adherence.

The overall retention rate in the study was high; as many as 97% of the quarterly follow-up visits were completed, including 95% in the Doxy PEP group and 98% of the standard care group. The response rate for the weekly surveys was 81%.

Of note, women reported the use of the treatment to be “imperfect,” suggesting social problems, such as biases toward the use of the prophylaxis.

The results underscore the need for ongoing efforts to make sure no groups of patients are left behind as interventions advance, Dr. Stewart said.

“The burden of STIs on cisgender women is large and growing,” she concluded. “STI prevention interventions are needed.”

Commenting on the study, Renee A. Heffron, PhD, MPH, said the findings “are somewhat surprising because results from trials in other populations have been positive.

“But cisgender women are exposed through the cervix, and this tissue is different from rectal or urethral tissue,” Dr. Heffron, a professor at the department of medicine and director of the Center for AIDS Research at the University of Alabama, Birmingham, told this news organization.

Further findings from the research should help shed light on key issues of adherence and drug concentration levels in cervical tissue, she added.

“For cisgender women, these data are the first and the beginning of understanding whether this is a viable strategy,” Dr. Heffron said.

“We have more to learn to better understand the results from the trial main outcomes, and if there are tweaks to this strategy that would improve efficacy.”

The authors and Dr. Heffron have disclosed no relevant financial relationships.

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

The benefits of doxycycline postexposure prophylaxis (Doxy PEP) in preventing the transmission of sexually transmitted infections (STIs) in men and transgender women do not appear to extend to cisgender women, who have disproportionately high rates of infection in many regions.

“This was the first trial to evaluate doxycycline PEP for cisgender women,” said first author Jenell Stewart, DO, of the University of Minnesota, Minneapolis, in discussing the findings at a press conference at the Conference on Retroviruses & Opportunistic Infections.

“Unfortunately, our primary outcome was not statistically significant – we did not see a reduction in STIs among cisgender women, which is in stark contrast to [reported effects] among cisgender men and transgender women,” she said.

The findings are from a study of 449 nonpregnant cisgender women (mean age, 24 years) in Kenya who had been taking daily oral HIV preexposure prophylaxis (PrEP) for a median of about 7 months.

The women were randomly assigned to receive either Doxy PEP 200 mg, to be taken within 72 hours of sex (n = 224), or standard care, which included quarterly screening and treatment of STIs (n = 225).

Of the women, 36.7% reported transactional sex at enrollment; their baseline prevalence of STIs was 17.9%, including 14.1% with chlamydia, 3.8% gonorrhea, and 0.4% syphilis. There were no differences between the study groups.

In surveys, 78% of the women reported adherence to the use of Doxy PEP; they took the prophylaxis at least as many days as they had sex.

Nevertheless, there was no significant difference in the incidence of STIs, reported over 1 year, at quarterly visits that included genital STI testing, between groups, with 50 patients in the Doxy PEP group and 59 in the standard screening group developing STIs (relative risk, 0.88; P = .51).

Of the infections, 85 were chlamydia, including 35 in the Doxy PEP group and 50 with standard of care, while 31 were gonorrhea, including 19 in the Doxy PEP group and 12 with standard of care; 8 had both infections, and there was 1 syphilis infection.

The results were consistent across subanalyses of patients grouped according to STI, who became pregnant (n = 80), or sorted by other factors including age, contraceptive use, transactional sex, and STI at baseline.

None of the women developed HIV, and there were no serious events associated with the Doxy PEP treatment.
 

Cisgender women bear ‘highest burden’ of STIs

The findings are disappointing in light of the higher rates of STIs among cisgender women, with the Centers for Disease Control and Prevention reporting that women also disproportionately bear the long-term consequences of STIs.

“For example, each year, untreated sexually transmitted diseases cause infertility in at least 20,000 women in the United States, and a pregnant woman is highly likely to pass syphilis unto her unborn baby if left untested or untreated,” the CDC reports.

The STI rates are particularly high for women taking HIV PrEP in regions like East Africa, where rates of STIs among cisgender women in many cases are higher than rates for men taking PrEP in high income countries, Dr. Stewart said.

Previous studies of Doxy PEP in men and transgender women taking HIV PrEP, including new research presented at CROI, have shown highly encouraging reductions in STIs, at rates of up to approximately 80% for chlamydia and syphilis.
 

Adherence, anatomy, resistance

The key theories for the lack of a prevention of infections in cisgender women surround the issues of resistances, as well as anatomy and adherence, said Dr. Stewart.

In terms of bacterial resistances, while initial testing in a limited number of samples the study found no evidence of markers of resistance for chlamydia, all of the gonorrhea samples did show tetracycline-resistant N gonorrhea at baseline and follow-up in both groups.

Regarding anatomic differences, doxycycline may not prevent STIs in endocervical tissue among cisgender women, Dr. Stewart noted. Women are known to be at higher risk of infection because the lining of the vagina is thinner than the skin of the penis, allowing for easier penetration of bacteria and viruses.

The study was designed to optimize adherence to Doxy PEP. Measures included monitoring with weekly text message surveys, in which the women reported a high rate of adherence.

The overall retention rate in the study was high; as many as 97% of the quarterly follow-up visits were completed, including 95% in the Doxy PEP group and 98% of the standard care group. The response rate for the weekly surveys was 81%.

Of note, women reported the use of the treatment to be “imperfect,” suggesting social problems, such as biases toward the use of the prophylaxis.

The results underscore the need for ongoing efforts to make sure no groups of patients are left behind as interventions advance, Dr. Stewart said.

“The burden of STIs on cisgender women is large and growing,” she concluded. “STI prevention interventions are needed.”

Commenting on the study, Renee A. Heffron, PhD, MPH, said the findings “are somewhat surprising because results from trials in other populations have been positive.

“But cisgender women are exposed through the cervix, and this tissue is different from rectal or urethral tissue,” Dr. Heffron, a professor at the department of medicine and director of the Center for AIDS Research at the University of Alabama, Birmingham, told this news organization.

Further findings from the research should help shed light on key issues of adherence and drug concentration levels in cervical tissue, she added.

“For cisgender women, these data are the first and the beginning of understanding whether this is a viable strategy,” Dr. Heffron said.

“We have more to learn to better understand the results from the trial main outcomes, and if there are tweaks to this strategy that would improve efficacy.”

The authors and Dr. Heffron have disclosed no relevant financial relationships.

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

The latest study to show high efficacy of doxycycline post-exposure prophylaxis (Doxy PEP) in preventing sexually transmitted infections among men who have sex with men (MSM) adds a new twist, showing – for the first time – reductions in gonorrhea among those receiving the meningococcal B vaccine.

“Among men who have sex with men on HIV PrEP, doxycycline PEP significantly reduced the incidence of chlamydia and syphilis and also had a significant impact on the incidence of gonorrhea,” said first author Jean-Michel Molina, MD, PhD, in presenting the findings at the Conference on Retroviruses and Opportunistic Infections.

In addition, “two doses of the meningococcal B vaccine reduced the incidence of a first episode of gonorrhea by roughly 50% among men who have sex with men,” said Dr. Molina, a professor of infectious diseases at the University of Paris, and head of the Infectious Diseases Department at the Saint-Louis and Lariboisière Hospitals, Paris.

Whereas the advent of PrEP has been associated with significant reductions in HIV transmission, rates of STIs have conversely been on the rise among MSM, specifically among those receiving PrEP.

Post-exposure prophylaxis with Doxy PEP has been shown to reduce the incidence of chlamydia and syphilis by approximately 70%; however, effects on prevention of gonorrhea have been less clear.

Meningococcal B vaccination has, meanwhile, shown intriguing reductions of gonorrhea incidence of as much as 26%-46% in some observational studies.

Therefore, Dr. Molina and colleagues decided to further investigate Doxy PEP as well as the meningococcal B vaccine in prevention of STIs.

For the ANRS 174 DOXYVAC trial, they enrolled 546 MSM in the open-label, multicenter study between January 2021 and July 2022.

The men were randomly assigned to one of 4 groups: doxycycline postexposure prophylaxis (Doxy PEP: 200 mg; n = 332), no Doxy PEP (n = 170), two shots of meningococcal B vaccine (4CMenB vaccine; n = 257), or no 4CMenB vaccine (n = 245).

All participants were assigned to their groups within 72 hours of condomless sex.

The men, who had a median age of 39, had a median time of PrEP use of 42 months, a history of an STI in the past year, and their median number of sexual partners in the past 3 months was 10.

Their characteristics were well-balanced across the treatment groups. After discontinuations of 54 patients across the groups, the final analysis included 502 participants.

With a median follow-up of 9 months, the intent-to-treat analysis showed 13 subjects had a first episode of chlamydia or syphilis in the Doxy PEP group, versus 49 subjects infected in the no Doxy PEP arm, for an incidence of 5.6 versus 35.4 per 100 person-years, respectively (adjusted hazard ratio, 0.16; P < .0001).

Infection specifically with chlamydia occurred among 21 men with no Doxy PEP versus 5 receiving Dox PEP (19.3 vs. 2.1 per 100 person-years, respectively; HR, 0.11; P < .0001).

And infection with syphilis occurred in 18 men receiving no Doxy PEP versus 8 receiving the treatment (16.3 vs. 3.4 per 100 person-years, respectively; HR, 0.21; P < .001).

The corresponding rates for gonorrhea infection were an incidence 41.3 versus 20.5 per 100 person-years, in the no Doxy PEP versus Doxy PEP arms, respectively (adjusted HR, 0.49; P = .001), and 29.4 versus 16.8 per 100 person-years for Mycoplasma genitalium infection (aHR, 0.55; P = .015).

Throughout the study, about 80% of patients in the Doxy PEP group reported using the prophylaxis treatment after their most recent sexual intercourse, with subjects reporting taking a median of seven pills per month.

In the vaccine/no vaccine comparisons, 32 subjects in the no meningococcal vaccine group were infected with a first gonorrhea infection, compared with 17 in the vaccine group, representing an incidence of 19.7 versus 9.8 per 100 person-years, respectively (adjusted HR, 0.49; P = .016), which Dr. Molina called “highly significant.”

An analysis of the cumulative incidence of gonorrhea infection with the meningococcal vaccine showed rates in the no vaccine versus vaccine groups of 30.4 versus 20.1 per 100 person-years, respectively; however, statistical significance was not reached (aHR, 0.66; P = .052).

Importantly, there were no significant interactions in the results between those receiving Doxy PEP or the 4CMenB vaccine group, and there were no significant differences in drug-related serious adverse events between the groups.

Dr. Molina noted that the meningococcal B vaccine is known to contain key antigens that are shared between meningitis and gonorrhea, which could explain the benefits.

Although chlamydia and syphilis thus far appear to remain susceptible to Doxy PEP, resistances with gonorrhea remain a concern, hence the ability of the vaccine to provide some protection could be an added bonus.

“We know that [gonorrhea] is able to very quickly develop resistances to any antibiotics, so that was why we wanted to look beyond the antibiotic prophylaxis,” said Dr. Molina.

Among questions to explore looking ahead is the potential longevity of protection with the vaccine.

“We don’t know at this point how long the protection with the vaccine could last, or if [people] may need booster injections, for instance, but the literature suggests benefits for at least a year,” Dr. Molina said. “We are still monitoring the patients in the study to see what happens.”

He added that combination of the interventions may be of benefit.

“In the future, we think we may need to combine these approaches if we want to meet the WHO/UNAIDS targets to reduce the incidence of HIV and STIs by 90% by 2030.”

Commenting on the study, CROI vice-chair Landon Myer, MD, PhD, noted that “gonorrhea develops resistance quickly and can be hard to treat or prophylaxis, so the vaccine finding, which was hinted at by previous observational data, is really important.”

He agrees that “the duration of protective efficacy – a big thing in vaccines – is unknown.”

“Still, this is really significant,” Dr. Myer stressed. “An efficacious vaccine against a stubborn sexually transmitted infection.”

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

The latest study to show high efficacy of doxycycline post-exposure prophylaxis (Doxy PEP) in preventing sexually transmitted infections among men who have sex with men (MSM) adds a new twist, showing – for the first time – reductions in gonorrhea among those receiving the meningococcal B vaccine.

“Among men who have sex with men on HIV PrEP, doxycycline PEP significantly reduced the incidence of chlamydia and syphilis and also had a significant impact on the incidence of gonorrhea,” said first author Jean-Michel Molina, MD, PhD, in presenting the findings at the Conference on Retroviruses and Opportunistic Infections.

In addition, “two doses of the meningococcal B vaccine reduced the incidence of a first episode of gonorrhea by roughly 50% among men who have sex with men,” said Dr. Molina, a professor of infectious diseases at the University of Paris, and head of the Infectious Diseases Department at the Saint-Louis and Lariboisière Hospitals, Paris.

Whereas the advent of PrEP has been associated with significant reductions in HIV transmission, rates of STIs have conversely been on the rise among MSM, specifically among those receiving PrEP.

Post-exposure prophylaxis with Doxy PEP has been shown to reduce the incidence of chlamydia and syphilis by approximately 70%; however, effects on prevention of gonorrhea have been less clear.

Meningococcal B vaccination has, meanwhile, shown intriguing reductions of gonorrhea incidence of as much as 26%-46% in some observational studies.

Therefore, Dr. Molina and colleagues decided to further investigate Doxy PEP as well as the meningococcal B vaccine in prevention of STIs.

For the ANRS 174 DOXYVAC trial, they enrolled 546 MSM in the open-label, multicenter study between January 2021 and July 2022.

The men were randomly assigned to one of 4 groups: doxycycline postexposure prophylaxis (Doxy PEP: 200 mg; n = 332), no Doxy PEP (n = 170), two shots of meningococcal B vaccine (4CMenB vaccine; n = 257), or no 4CMenB vaccine (n = 245).

All participants were assigned to their groups within 72 hours of condomless sex.

The men, who had a median age of 39, had a median time of PrEP use of 42 months, a history of an STI in the past year, and their median number of sexual partners in the past 3 months was 10.

Their characteristics were well-balanced across the treatment groups. After discontinuations of 54 patients across the groups, the final analysis included 502 participants.

With a median follow-up of 9 months, the intent-to-treat analysis showed 13 subjects had a first episode of chlamydia or syphilis in the Doxy PEP group, versus 49 subjects infected in the no Doxy PEP arm, for an incidence of 5.6 versus 35.4 per 100 person-years, respectively (adjusted hazard ratio, 0.16; P < .0001).

Infection specifically with chlamydia occurred among 21 men with no Doxy PEP versus 5 receiving Dox PEP (19.3 vs. 2.1 per 100 person-years, respectively; HR, 0.11; P < .0001).

And infection with syphilis occurred in 18 men receiving no Doxy PEP versus 8 receiving the treatment (16.3 vs. 3.4 per 100 person-years, respectively; HR, 0.21; P < .001).

The corresponding rates for gonorrhea infection were an incidence 41.3 versus 20.5 per 100 person-years, in the no Doxy PEP versus Doxy PEP arms, respectively (adjusted HR, 0.49; P = .001), and 29.4 versus 16.8 per 100 person-years for Mycoplasma genitalium infection (aHR, 0.55; P = .015).

Throughout the study, about 80% of patients in the Doxy PEP group reported using the prophylaxis treatment after their most recent sexual intercourse, with subjects reporting taking a median of seven pills per month.

In the vaccine/no vaccine comparisons, 32 subjects in the no meningococcal vaccine group were infected with a first gonorrhea infection, compared with 17 in the vaccine group, representing an incidence of 19.7 versus 9.8 per 100 person-years, respectively (adjusted HR, 0.49; P = .016), which Dr. Molina called “highly significant.”

An analysis of the cumulative incidence of gonorrhea infection with the meningococcal vaccine showed rates in the no vaccine versus vaccine groups of 30.4 versus 20.1 per 100 person-years, respectively; however, statistical significance was not reached (aHR, 0.66; P = .052).

Importantly, there were no significant interactions in the results between those receiving Doxy PEP or the 4CMenB vaccine group, and there were no significant differences in drug-related serious adverse events between the groups.

Dr. Molina noted that the meningococcal B vaccine is known to contain key antigens that are shared between meningitis and gonorrhea, which could explain the benefits.

Although chlamydia and syphilis thus far appear to remain susceptible to Doxy PEP, resistances with gonorrhea remain a concern, hence the ability of the vaccine to provide some protection could be an added bonus.

“We know that [gonorrhea] is able to very quickly develop resistances to any antibiotics, so that was why we wanted to look beyond the antibiotic prophylaxis,” said Dr. Molina.

Among questions to explore looking ahead is the potential longevity of protection with the vaccine.

“We don’t know at this point how long the protection with the vaccine could last, or if [people] may need booster injections, for instance, but the literature suggests benefits for at least a year,” Dr. Molina said. “We are still monitoring the patients in the study to see what happens.”

He added that combination of the interventions may be of benefit.

“In the future, we think we may need to combine these approaches if we want to meet the WHO/UNAIDS targets to reduce the incidence of HIV and STIs by 90% by 2030.”

Commenting on the study, CROI vice-chair Landon Myer, MD, PhD, noted that “gonorrhea develops resistance quickly and can be hard to treat or prophylaxis, so the vaccine finding, which was hinted at by previous observational data, is really important.”

He agrees that “the duration of protective efficacy – a big thing in vaccines – is unknown.”

“Still, this is really significant,” Dr. Myer stressed. “An efficacious vaccine against a stubborn sexually transmitted infection.”

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

The latest study to show high efficacy of doxycycline post-exposure prophylaxis (Doxy PEP) in preventing sexually transmitted infections among men who have sex with men (MSM) adds a new twist, showing – for the first time – reductions in gonorrhea among those receiving the meningococcal B vaccine.

“Among men who have sex with men on HIV PrEP, doxycycline PEP significantly reduced the incidence of chlamydia and syphilis and also had a significant impact on the incidence of gonorrhea,” said first author Jean-Michel Molina, MD, PhD, in presenting the findings at the Conference on Retroviruses and Opportunistic Infections.

In addition, “two doses of the meningococcal B vaccine reduced the incidence of a first episode of gonorrhea by roughly 50% among men who have sex with men,” said Dr. Molina, a professor of infectious diseases at the University of Paris, and head of the Infectious Diseases Department at the Saint-Louis and Lariboisière Hospitals, Paris.

Whereas the advent of PrEP has been associated with significant reductions in HIV transmission, rates of STIs have conversely been on the rise among MSM, specifically among those receiving PrEP.

Post-exposure prophylaxis with Doxy PEP has been shown to reduce the incidence of chlamydia and syphilis by approximately 70%; however, effects on prevention of gonorrhea have been less clear.

Meningococcal B vaccination has, meanwhile, shown intriguing reductions of gonorrhea incidence of as much as 26%-46% in some observational studies.

Therefore, Dr. Molina and colleagues decided to further investigate Doxy PEP as well as the meningococcal B vaccine in prevention of STIs.

For the ANRS 174 DOXYVAC trial, they enrolled 546 MSM in the open-label, multicenter study between January 2021 and July 2022.

The men were randomly assigned to one of 4 groups: doxycycline postexposure prophylaxis (Doxy PEP: 200 mg; n = 332), no Doxy PEP (n = 170), two shots of meningococcal B vaccine (4CMenB vaccine; n = 257), or no 4CMenB vaccine (n = 245).

All participants were assigned to their groups within 72 hours of condomless sex.

The men, who had a median age of 39, had a median time of PrEP use of 42 months, a history of an STI in the past year, and their median number of sexual partners in the past 3 months was 10.

Their characteristics were well-balanced across the treatment groups. After discontinuations of 54 patients across the groups, the final analysis included 502 participants.

With a median follow-up of 9 months, the intent-to-treat analysis showed 13 subjects had a first episode of chlamydia or syphilis in the Doxy PEP group, versus 49 subjects infected in the no Doxy PEP arm, for an incidence of 5.6 versus 35.4 per 100 person-years, respectively (adjusted hazard ratio, 0.16; P < .0001).

Infection specifically with chlamydia occurred among 21 men with no Doxy PEP versus 5 receiving Dox PEP (19.3 vs. 2.1 per 100 person-years, respectively; HR, 0.11; P < .0001).

And infection with syphilis occurred in 18 men receiving no Doxy PEP versus 8 receiving the treatment (16.3 vs. 3.4 per 100 person-years, respectively; HR, 0.21; P < .001).

The corresponding rates for gonorrhea infection were an incidence 41.3 versus 20.5 per 100 person-years, in the no Doxy PEP versus Doxy PEP arms, respectively (adjusted HR, 0.49; P = .001), and 29.4 versus 16.8 per 100 person-years for Mycoplasma genitalium infection (aHR, 0.55; P = .015).

Throughout the study, about 80% of patients in the Doxy PEP group reported using the prophylaxis treatment after their most recent sexual intercourse, with subjects reporting taking a median of seven pills per month.

In the vaccine/no vaccine comparisons, 32 subjects in the no meningococcal vaccine group were infected with a first gonorrhea infection, compared with 17 in the vaccine group, representing an incidence of 19.7 versus 9.8 per 100 person-years, respectively (adjusted HR, 0.49; P = .016), which Dr. Molina called “highly significant.”

An analysis of the cumulative incidence of gonorrhea infection with the meningococcal vaccine showed rates in the no vaccine versus vaccine groups of 30.4 versus 20.1 per 100 person-years, respectively; however, statistical significance was not reached (aHR, 0.66; P = .052).

Importantly, there were no significant interactions in the results between those receiving Doxy PEP or the 4CMenB vaccine group, and there were no significant differences in drug-related serious adverse events between the groups.

Dr. Molina noted that the meningococcal B vaccine is known to contain key antigens that are shared between meningitis and gonorrhea, which could explain the benefits.

Although chlamydia and syphilis thus far appear to remain susceptible to Doxy PEP, resistances with gonorrhea remain a concern, hence the ability of the vaccine to provide some protection could be an added bonus.

“We know that [gonorrhea] is able to very quickly develop resistances to any antibiotics, so that was why we wanted to look beyond the antibiotic prophylaxis,” said Dr. Molina.

Among questions to explore looking ahead is the potential longevity of protection with the vaccine.

“We don’t know at this point how long the protection with the vaccine could last, or if [people] may need booster injections, for instance, but the literature suggests benefits for at least a year,” Dr. Molina said. “We are still monitoring the patients in the study to see what happens.”

He added that combination of the interventions may be of benefit.

“In the future, we think we may need to combine these approaches if we want to meet the WHO/UNAIDS targets to reduce the incidence of HIV and STIs by 90% by 2030.”

Commenting on the study, CROI vice-chair Landon Myer, MD, PhD, noted that “gonorrhea develops resistance quickly and can be hard to treat or prophylaxis, so the vaccine finding, which was hinted at by previous observational data, is really important.”

He agrees that “the duration of protective efficacy – a big thing in vaccines – is unknown.”

“Still, this is really significant,” Dr. Myer stressed. “An efficacious vaccine against a stubborn sexually transmitted infection.”

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

Treatment with the diabetes drug metformin shows a significant, dose-dependent effect in lowering SARS-CoV-2 viral load within days of administration, according to the latest analysis of the phase 3 COVID-OUT trial. These findings add to a multitude of benefits the drug has been shown to have in COVID infection.

COVID-OUT did not meet its primary endpoint, but it did show important secondary outcomes including a 42% reduction in ED visits and in hospitalizations and/or deaths by day 14, and a 58% reduction in hospitalizations/death by day 28. A further subanalysis has shown a 42% reduction in long COVID, compared with placebo.

“In this phase 3 randomized controlled trial, metformin showed prevention of severe COVID, prevention of long COVID, and an antiviral effect, and this is consistent with other data,” said coauthor Carolyn Bramante, MD, University of Minnesota, Minneapolis, in presenting the findings at the Conference on Retroviruses & Opportunistic Infections.
 

Study details

For the new subanalysis, the authors further evaluated the effects of metformin treatment on SARS-CoV-2 viral load.

A total of 1,323 patients in the study, enrolled at six centers, were randomized to treatment either with metformin 1,000 mg per day on days 2-5 and 1,500 mg per day on days 6 to 14 (n = 187), or to ivermectin 390-470 mcg/kg per day for 3 days (n = 187), fluvoxamine 50 mg twice daily for 14 days, and/or an exact-matching placebo in a 2 x 3 factorial trial design.

The subanalysis on viral load included 483 patients from the trial who were treated with metformin versus 462 who received placebo, who were all enrolled within 3 days of a documented SARS-CoV-2 infection and less than 7 days after symptom onset.

The patients had a median age of 46 years, and all had either overweight or obesity. Only about 2% had diabetes, and only patients considered low-risk were excluded from the trial, including those under age 30 and those with a body mass index under 25.

About half of patients had received a primary vaccine and about 5% had received a vaccine booster. SARS-CoV-2 variants that were prominent during the study included Alpha, Delta, and Omicron.

The viral samples available on days 1, 5, and 10 showed a mean change in viral load from baseline to follow-up; the viral load was significantly lower with metformin versus placebo (–0.64 log10 copies/mL), representing a 4.4-fold greater decrease in viral load with metformin.

The mean rate of undetectable SARS-CoV-2 viral load at day 5 was 49.9% in the metformin group versus 54.6% in the placebo group (odds ratio, 1.235), and the undetectable rate at day 10 was 14.3% in the metformin group and 22.6% in the placebo group (OR, 1.663; P = .003).

An increased antiviral effect corresponded with increases in metformin dosing on days 6 through 14. Furthermore, the antiviral effect became stronger when metformin was started earlier in the course of infection.

Of note, the antiviral effect was more pronounced among those who were not vaccinated (mean, –0.95 log copies/mL), compared with the vaccinated (mean, –0.39 log copies/mL).

The antiviral effect with metformin was similar to that seen with nirmatrelvir at day 5 and was greater than nirmatrelvir at day 10.

No similar relationships in SARS-CoV-2 viral load were observed between ivermectin or fluvoxamine and placebo.

The findings are consistent with results of other recent observational studies, including research showing metformin to be associated with reductions in COVID-19 severity in patients with prediabetes, Dr. Bramante noted.

The authors’ previous analysis looking at long COVID in the COVID-OUT study showed that metformin treatment during acute COVID significantly reduced the risk for a diagnosis of long COVID versus placebo at 300 days following randomization, with a hazard ratio of 0.59 after adjustment for the study drug and vaccination at baseline.

Dr. Bramante noted that metformin’s potential antiviral properties have long been speculated, with some of the earliest research on the drug suggesting less severe outcomes in influenza, and more recently, RNA assays suggesting effects against other RNA viruses, including the Zika virus.

In terms of COVID, Dr. Bramante noted that the drug has plenty of potentially favorable benefits.

“Metformin is very safe and is known to have very few contraindications, so the next steps could be to consider looking at this in terms of a combination therapy,” she said.
 

‘Data from other studies are conflicting’

Commenting on the study, Diane V. Havlir, MD, cautioned that “metformin is currently not recommended in treatment guidelines, [and] data from other studies are conflicting; side effects can be an issue, and the study presented here was in a select population,” she said in an interview.

However, “what is both new and interesting in this presentation is the reduction of viral load, which [was observed] in the samples collected not only on days 1-5, but also days 6-14,” said Dr. Havlir, who is professor and associate chair of clinical research, department of medicine, and chief of the division of HIV, infectious diseases and global medicine and director of the AIDS Research Institute at the University of California, San Francisco.

Key questions the findings raise include whether the results correlate with clinical outcomes or transmission, and whether the findings are generalizable to other populations and settings, Dr. Havlir said.

Ultimately, “we need to continue to pursue all aspects of outpatient treatments for COVID to address questions like these for new and existing agents,” she added.

The trial received funding from the Parsemus Foundation, the Rainwater Charitable Foundation, Fast Grants, and the United Health Group. The authors and Dr. Havlir disclosed no relevant financial relationships.

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

Treatment with the diabetes drug metformin shows a significant, dose-dependent effect in lowering SARS-CoV-2 viral load within days of administration, according to the latest analysis of the phase 3 COVID-OUT trial. These findings add to a multitude of benefits the drug has been shown to have in COVID infection.

COVID-OUT did not meet its primary endpoint, but it did show important secondary outcomes including a 42% reduction in ED visits and in hospitalizations and/or deaths by day 14, and a 58% reduction in hospitalizations/death by day 28. A further subanalysis has shown a 42% reduction in long COVID, compared with placebo.

“In this phase 3 randomized controlled trial, metformin showed prevention of severe COVID, prevention of long COVID, and an antiviral effect, and this is consistent with other data,” said coauthor Carolyn Bramante, MD, University of Minnesota, Minneapolis, in presenting the findings at the Conference on Retroviruses & Opportunistic Infections.
 

Study details

For the new subanalysis, the authors further evaluated the effects of metformin treatment on SARS-CoV-2 viral load.

A total of 1,323 patients in the study, enrolled at six centers, were randomized to treatment either with metformin 1,000 mg per day on days 2-5 and 1,500 mg per day on days 6 to 14 (n = 187), or to ivermectin 390-470 mcg/kg per day for 3 days (n = 187), fluvoxamine 50 mg twice daily for 14 days, and/or an exact-matching placebo in a 2 x 3 factorial trial design.

The subanalysis on viral load included 483 patients from the trial who were treated with metformin versus 462 who received placebo, who were all enrolled within 3 days of a documented SARS-CoV-2 infection and less than 7 days after symptom onset.

The patients had a median age of 46 years, and all had either overweight or obesity. Only about 2% had diabetes, and only patients considered low-risk were excluded from the trial, including those under age 30 and those with a body mass index under 25.

About half of patients had received a primary vaccine and about 5% had received a vaccine booster. SARS-CoV-2 variants that were prominent during the study included Alpha, Delta, and Omicron.

The viral samples available on days 1, 5, and 10 showed a mean change in viral load from baseline to follow-up; the viral load was significantly lower with metformin versus placebo (–0.64 log10 copies/mL), representing a 4.4-fold greater decrease in viral load with metformin.

The mean rate of undetectable SARS-CoV-2 viral load at day 5 was 49.9% in the metformin group versus 54.6% in the placebo group (odds ratio, 1.235), and the undetectable rate at day 10 was 14.3% in the metformin group and 22.6% in the placebo group (OR, 1.663; P = .003).

An increased antiviral effect corresponded with increases in metformin dosing on days 6 through 14. Furthermore, the antiviral effect became stronger when metformin was started earlier in the course of infection.

Of note, the antiviral effect was more pronounced among those who were not vaccinated (mean, –0.95 log copies/mL), compared with the vaccinated (mean, –0.39 log copies/mL).

The antiviral effect with metformin was similar to that seen with nirmatrelvir at day 5 and was greater than nirmatrelvir at day 10.

No similar relationships in SARS-CoV-2 viral load were observed between ivermectin or fluvoxamine and placebo.

The findings are consistent with results of other recent observational studies, including research showing metformin to be associated with reductions in COVID-19 severity in patients with prediabetes, Dr. Bramante noted.

The authors’ previous analysis looking at long COVID in the COVID-OUT study showed that metformin treatment during acute COVID significantly reduced the risk for a diagnosis of long COVID versus placebo at 300 days following randomization, with a hazard ratio of 0.59 after adjustment for the study drug and vaccination at baseline.

Dr. Bramante noted that metformin’s potential antiviral properties have long been speculated, with some of the earliest research on the drug suggesting less severe outcomes in influenza, and more recently, RNA assays suggesting effects against other RNA viruses, including the Zika virus.

In terms of COVID, Dr. Bramante noted that the drug has plenty of potentially favorable benefits.

“Metformin is very safe and is known to have very few contraindications, so the next steps could be to consider looking at this in terms of a combination therapy,” she said.
 

‘Data from other studies are conflicting’

Commenting on the study, Diane V. Havlir, MD, cautioned that “metformin is currently not recommended in treatment guidelines, [and] data from other studies are conflicting; side effects can be an issue, and the study presented here was in a select population,” she said in an interview.

However, “what is both new and interesting in this presentation is the reduction of viral load, which [was observed] in the samples collected not only on days 1-5, but also days 6-14,” said Dr. Havlir, who is professor and associate chair of clinical research, department of medicine, and chief of the division of HIV, infectious diseases and global medicine and director of the AIDS Research Institute at the University of California, San Francisco.

Key questions the findings raise include whether the results correlate with clinical outcomes or transmission, and whether the findings are generalizable to other populations and settings, Dr. Havlir said.

Ultimately, “we need to continue to pursue all aspects of outpatient treatments for COVID to address questions like these for new and existing agents,” she added.

The trial received funding from the Parsemus Foundation, the Rainwater Charitable Foundation, Fast Grants, and the United Health Group. The authors and Dr. Havlir disclosed no relevant financial relationships.

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

Treatment with the diabetes drug metformin shows a significant, dose-dependent effect in lowering SARS-CoV-2 viral load within days of administration, according to the latest analysis of the phase 3 COVID-OUT trial. These findings add to a multitude of benefits the drug has been shown to have in COVID infection.

COVID-OUT did not meet its primary endpoint, but it did show important secondary outcomes including a 42% reduction in ED visits and in hospitalizations and/or deaths by day 14, and a 58% reduction in hospitalizations/death by day 28. A further subanalysis has shown a 42% reduction in long COVID, compared with placebo.

“In this phase 3 randomized controlled trial, metformin showed prevention of severe COVID, prevention of long COVID, and an antiviral effect, and this is consistent with other data,” said coauthor Carolyn Bramante, MD, University of Minnesota, Minneapolis, in presenting the findings at the Conference on Retroviruses & Opportunistic Infections.
 

Study details

For the new subanalysis, the authors further evaluated the effects of metformin treatment on SARS-CoV-2 viral load.

A total of 1,323 patients in the study, enrolled at six centers, were randomized to treatment either with metformin 1,000 mg per day on days 2-5 and 1,500 mg per day on days 6 to 14 (n = 187), or to ivermectin 390-470 mcg/kg per day for 3 days (n = 187), fluvoxamine 50 mg twice daily for 14 days, and/or an exact-matching placebo in a 2 x 3 factorial trial design.

The subanalysis on viral load included 483 patients from the trial who were treated with metformin versus 462 who received placebo, who were all enrolled within 3 days of a documented SARS-CoV-2 infection and less than 7 days after symptom onset.

The patients had a median age of 46 years, and all had either overweight or obesity. Only about 2% had diabetes, and only patients considered low-risk were excluded from the trial, including those under age 30 and those with a body mass index under 25.

About half of patients had received a primary vaccine and about 5% had received a vaccine booster. SARS-CoV-2 variants that were prominent during the study included Alpha, Delta, and Omicron.

The viral samples available on days 1, 5, and 10 showed a mean change in viral load from baseline to follow-up; the viral load was significantly lower with metformin versus placebo (–0.64 log10 copies/mL), representing a 4.4-fold greater decrease in viral load with metformin.

The mean rate of undetectable SARS-CoV-2 viral load at day 5 was 49.9% in the metformin group versus 54.6% in the placebo group (odds ratio, 1.235), and the undetectable rate at day 10 was 14.3% in the metformin group and 22.6% in the placebo group (OR, 1.663; P = .003).

An increased antiviral effect corresponded with increases in metformin dosing on days 6 through 14. Furthermore, the antiviral effect became stronger when metformin was started earlier in the course of infection.

Of note, the antiviral effect was more pronounced among those who were not vaccinated (mean, –0.95 log copies/mL), compared with the vaccinated (mean, –0.39 log copies/mL).

The antiviral effect with metformin was similar to that seen with nirmatrelvir at day 5 and was greater than nirmatrelvir at day 10.

No similar relationships in SARS-CoV-2 viral load were observed between ivermectin or fluvoxamine and placebo.

The findings are consistent with results of other recent observational studies, including research showing metformin to be associated with reductions in COVID-19 severity in patients with prediabetes, Dr. Bramante noted.

The authors’ previous analysis looking at long COVID in the COVID-OUT study showed that metformin treatment during acute COVID significantly reduced the risk for a diagnosis of long COVID versus placebo at 300 days following randomization, with a hazard ratio of 0.59 after adjustment for the study drug and vaccination at baseline.

Dr. Bramante noted that metformin’s potential antiviral properties have long been speculated, with some of the earliest research on the drug suggesting less severe outcomes in influenza, and more recently, RNA assays suggesting effects against other RNA viruses, including the Zika virus.

In terms of COVID, Dr. Bramante noted that the drug has plenty of potentially favorable benefits.

“Metformin is very safe and is known to have very few contraindications, so the next steps could be to consider looking at this in terms of a combination therapy,” she said.
 

‘Data from other studies are conflicting’

Commenting on the study, Diane V. Havlir, MD, cautioned that “metformin is currently not recommended in treatment guidelines, [and] data from other studies are conflicting; side effects can be an issue, and the study presented here was in a select population,” she said in an interview.

However, “what is both new and interesting in this presentation is the reduction of viral load, which [was observed] in the samples collected not only on days 1-5, but also days 6-14,” said Dr. Havlir, who is professor and associate chair of clinical research, department of medicine, and chief of the division of HIV, infectious diseases and global medicine and director of the AIDS Research Institute at the University of California, San Francisco.

Key questions the findings raise include whether the results correlate with clinical outcomes or transmission, and whether the findings are generalizable to other populations and settings, Dr. Havlir said.

Ultimately, “we need to continue to pursue all aspects of outpatient treatments for COVID to address questions like these for new and existing agents,” she added.

The trial received funding from the Parsemus Foundation, the Rainwater Charitable Foundation, Fast Grants, and the United Health Group. The authors and Dr. Havlir disclosed no relevant financial relationships.

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

A strategy for the treatment of tuberculosis involving just an 8-week treatment regimen – along with close posttreatment monitoring and treatment extension if needed – shows potential as an effective alternative to the standard 24-week regimen.

“We found that if we use the strategy of a bedaquiline-linezolid five-drug regimen for 8 weeks and then followed patients for 96 weeks, [the regimen] was noninferior, clinically, to the standard regimen in terms of the number of people alive, free of TB disease, and not on treatment,” said lead author Nicholas Paton, MD, of the National University of Singapore, in a press conference held during the Conference on Retroviruses & Opportunistic Infections.

“The total time on treatment was reduced by half – instead of 160 days, it was 85 days for the total duration.”

Commenting on the study, which was published concurrently in the New England Journal of Medicine, Richard E. Chaisson, MD, noted that, although more needs to be understood, the high number of responses is nevertheless encouraging.

“Clinicians will not feel comfortable with the short regimens at this point, but it is remarkable that so many patients did well with shorter treatments,” Dr. Chaisson, who is a professor of medicine, epidemiology, and international health and director of the Johns Hopkins University Center for Tuberculosis Research, Baltimore, said in an interview.

Importantly, the study should help push forward “future studies [that] will stratify patients according to their likelihood of responding to shorter treatments,” he said.

The current global standard for TB treatment, practiced for 4 decades, has been a 6-month rifampin-based regimen. Although the regimen performs well, curing more than 95% of cases in clinical trials, in real-world practice, the prolonged duration can be problematic, with issues of nonadherence and loss of patients to follow-up.

Previous research has shown that shorter regimens have potential, with some studies showing as many as 85% of patients cured with 3- and 4-month regimens, and some promising 2-month regimens showing efficacy specifically for those with smear-negative TB.

These efforts suggest that “the current 6-month regimen may lead to overtreatment in the majority of persons in order to prevent relapse in a minority of persons,” the authors asserted.
 

TRUNCATE-TB

To investigate a suitable shorter-term alternative, the authors conducted the phase 2-3, prospective, open-label TRUNCATE-TB trial, in which 674 patients with rifampin-susceptible pulmonary TB were enrolled at 18 sites in Asia and Africa.

The patients were randomly assigned to receive either the standard treatment regimen (rifampin and isoniazid for 24 weeks with pyrazinamide and ethambutol for the first 8 weeks; n = 181), or one of four novel five-drug regimens to be administered over 8 weeks, along with extended treatment for persistent clinical disease of up to 12 weeks, if needed, and a plan for retreatment in the case of relapse (n = 493).

Two of the regimens were dropped because of logistic criteria; the two remaining shorter-course groups included in the study involved either high-dose rifampin plus linezolid or bedaquiline plus linezolid, each combined with isoniazid, pyrazinamide, and ethambutol.

Of the patients, 62% were male, and four withdrew or were lost to follow-up by the end of the study at a final follow-up at week 96.

Among patients assigned to the 8-week regimens, 80% stopped at exactly 8 weeks, while 9% wound up having extended treatment to 10 weeks and 3% were extended to 12 weeks.

For the primary endpoint, a composite of death, ongoing treatment, or active disease at week 96, the rate was lowest in the standard 24-week therapy group, occurring in 7 of 181 patients (3.9%), compared with 21 of 184 patients (11.4%) in the rifampin plus linezolid group (adjusted difference, 7.4 percentage points, which did not meet noninferiority criterion), and 11 of 189 (5.8%) in the group in the bedaquiline plus linezolid group (adjusted difference, 0.8 percentage points, meeting noninferiority criterion).

The mean total duration of treatment through week 96 in the standard treatment group was 180 days versus 106 days in the rifampin–linezolid group, and 85 days in the bedaquiline-linezolid group.

The results were consistent across multiple subgroups defined according to baseline characteristics, including some that could be linked to severe disease and a high risk for relapse.

In terms of safety, there were no significant differences between the groups in terms of grade 3 or 4 adverse events.

Of note, only two patients (1.1%) in the bedaquiline plus linezolid group acquired a resistance, which Dr. Paton said was “encouraging,” because of concerns about resistance to that drug.
 

‘Unfavorable’ composite also evaluated

In an updated analysis of the study that Dr. Paton presented at the meeting, the authors looked at a revised “unfavorable” primary outcome – a composite including treatment failure, relapse, death, or nonattendance at week 96 without evidence of prior disease clearance.

The rate remained lowest in the standard 24-week therapy group (3.9%) versus 25% in the rifampin plus linezolid group, and 13.8% in the bedaquiline plus linezolid group.

Though the lower rate with the standard treatment was expected, Dr. Paton said the results nevertheless hold promise, at least for some patients, for successful treatment with the 8-week bedaquiline plus linezolid strategy.

“What the trial has told us is that even with that 13.8% relapse rate, we can manage patients within this strategy and people can do fine at the end, because with some simple clinical biomarkers, we can pick the people who may have a high chance of achieving a cure.”

Dr. Chaisson expressed concern over the higher unfavorable rates, but said the results help pave the way for refining a workable-shorter term strategy.

“TRUNCATE-TB did find that most patients could be successfully treated in 2 months with the novel regimen of bedaquiline plus linezolid, but the failure rate was still unacceptably high,” he said. 

“This regimen will not be widely adapted at this point, but additional analyses may identify subsets of patients who will do well with shorter regimens, and future studies will stratify patients according to their likelihood of responding to shorter treatments.”

The authors of an accompanying editorial further commented that the benefits of a shorter treatment strategy could very well outweigh possible shortcomings.

“Treatment algorithms such as that used in the TRUNCATE-TB trial are fundamental to tuberculosis control,” wrote Véronique Dartois, PhD, Center for Discovery and Innovation, Nutley, N.J., and Eric J. Rubin, MD, PhD, the editor-in-chief of NEJM. “Although implementing them could be a challenge, any added burden might be offset by reduced costs, better adherence, and increased patient satisfaction. Thus, for tuberculosis, a strategy might be more than just a regimen.”

The good news, as summed up by CROI vice-chair Landon Myer, MD, PhD, in the press conference, is that “we’re moving closer and closer to the holy grail of a short, efficacious regimen for TB treatment. We’re getting there slowly, but we’re getting there.”

The study received grant funding from the Singapore National Medical Research Council; a grant from the Department of Health and Social Care; the Foreign, Commonwealth, and Development Office; the Medical Research Council; and Wellcome Trust; as well as a grant from the UK Research and Innovation Medical Research Council. Dr. Dartois reported no relevant financial relationships. Dr. Chaisson had no disclosures to report.

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

A strategy for the treatment of tuberculosis involving just an 8-week treatment regimen – along with close posttreatment monitoring and treatment extension if needed – shows potential as an effective alternative to the standard 24-week regimen.

“We found that if we use the strategy of a bedaquiline-linezolid five-drug regimen for 8 weeks and then followed patients for 96 weeks, [the regimen] was noninferior, clinically, to the standard regimen in terms of the number of people alive, free of TB disease, and not on treatment,” said lead author Nicholas Paton, MD, of the National University of Singapore, in a press conference held during the Conference on Retroviruses & Opportunistic Infections.

“The total time on treatment was reduced by half – instead of 160 days, it was 85 days for the total duration.”

Commenting on the study, which was published concurrently in the New England Journal of Medicine, Richard E. Chaisson, MD, noted that, although more needs to be understood, the high number of responses is nevertheless encouraging.

“Clinicians will not feel comfortable with the short regimens at this point, but it is remarkable that so many patients did well with shorter treatments,” Dr. Chaisson, who is a professor of medicine, epidemiology, and international health and director of the Johns Hopkins University Center for Tuberculosis Research, Baltimore, said in an interview.

Importantly, the study should help push forward “future studies [that] will stratify patients according to their likelihood of responding to shorter treatments,” he said.

The current global standard for TB treatment, practiced for 4 decades, has been a 6-month rifampin-based regimen. Although the regimen performs well, curing more than 95% of cases in clinical trials, in real-world practice, the prolonged duration can be problematic, with issues of nonadherence and loss of patients to follow-up.

Previous research has shown that shorter regimens have potential, with some studies showing as many as 85% of patients cured with 3- and 4-month regimens, and some promising 2-month regimens showing efficacy specifically for those with smear-negative TB.

These efforts suggest that “the current 6-month regimen may lead to overtreatment in the majority of persons in order to prevent relapse in a minority of persons,” the authors asserted.
 

TRUNCATE-TB

To investigate a suitable shorter-term alternative, the authors conducted the phase 2-3, prospective, open-label TRUNCATE-TB trial, in which 674 patients with rifampin-susceptible pulmonary TB were enrolled at 18 sites in Asia and Africa.

The patients were randomly assigned to receive either the standard treatment regimen (rifampin and isoniazid for 24 weeks with pyrazinamide and ethambutol for the first 8 weeks; n = 181), or one of four novel five-drug regimens to be administered over 8 weeks, along with extended treatment for persistent clinical disease of up to 12 weeks, if needed, and a plan for retreatment in the case of relapse (n = 493).

Two of the regimens were dropped because of logistic criteria; the two remaining shorter-course groups included in the study involved either high-dose rifampin plus linezolid or bedaquiline plus linezolid, each combined with isoniazid, pyrazinamide, and ethambutol.

Of the patients, 62% were male, and four withdrew or were lost to follow-up by the end of the study at a final follow-up at week 96.

Among patients assigned to the 8-week regimens, 80% stopped at exactly 8 weeks, while 9% wound up having extended treatment to 10 weeks and 3% were extended to 12 weeks.

For the primary endpoint, a composite of death, ongoing treatment, or active disease at week 96, the rate was lowest in the standard 24-week therapy group, occurring in 7 of 181 patients (3.9%), compared with 21 of 184 patients (11.4%) in the rifampin plus linezolid group (adjusted difference, 7.4 percentage points, which did not meet noninferiority criterion), and 11 of 189 (5.8%) in the group in the bedaquiline plus linezolid group (adjusted difference, 0.8 percentage points, meeting noninferiority criterion).

The mean total duration of treatment through week 96 in the standard treatment group was 180 days versus 106 days in the rifampin–linezolid group, and 85 days in the bedaquiline-linezolid group.

The results were consistent across multiple subgroups defined according to baseline characteristics, including some that could be linked to severe disease and a high risk for relapse.

In terms of safety, there were no significant differences between the groups in terms of grade 3 or 4 adverse events.

Of note, only two patients (1.1%) in the bedaquiline plus linezolid group acquired a resistance, which Dr. Paton said was “encouraging,” because of concerns about resistance to that drug.
 

‘Unfavorable’ composite also evaluated

In an updated analysis of the study that Dr. Paton presented at the meeting, the authors looked at a revised “unfavorable” primary outcome – a composite including treatment failure, relapse, death, or nonattendance at week 96 without evidence of prior disease clearance.

The rate remained lowest in the standard 24-week therapy group (3.9%) versus 25% in the rifampin plus linezolid group, and 13.8% in the bedaquiline plus linezolid group.

Though the lower rate with the standard treatment was expected, Dr. Paton said the results nevertheless hold promise, at least for some patients, for successful treatment with the 8-week bedaquiline plus linezolid strategy.

“What the trial has told us is that even with that 13.8% relapse rate, we can manage patients within this strategy and people can do fine at the end, because with some simple clinical biomarkers, we can pick the people who may have a high chance of achieving a cure.”

Dr. Chaisson expressed concern over the higher unfavorable rates, but said the results help pave the way for refining a workable-shorter term strategy.

“TRUNCATE-TB did find that most patients could be successfully treated in 2 months with the novel regimen of bedaquiline plus linezolid, but the failure rate was still unacceptably high,” he said. 

“This regimen will not be widely adapted at this point, but additional analyses may identify subsets of patients who will do well with shorter regimens, and future studies will stratify patients according to their likelihood of responding to shorter treatments.”

The authors of an accompanying editorial further commented that the benefits of a shorter treatment strategy could very well outweigh possible shortcomings.

“Treatment algorithms such as that used in the TRUNCATE-TB trial are fundamental to tuberculosis control,” wrote Véronique Dartois, PhD, Center for Discovery and Innovation, Nutley, N.J., and Eric J. Rubin, MD, PhD, the editor-in-chief of NEJM. “Although implementing them could be a challenge, any added burden might be offset by reduced costs, better adherence, and increased patient satisfaction. Thus, for tuberculosis, a strategy might be more than just a regimen.”

The good news, as summed up by CROI vice-chair Landon Myer, MD, PhD, in the press conference, is that “we’re moving closer and closer to the holy grail of a short, efficacious regimen for TB treatment. We’re getting there slowly, but we’re getting there.”

The study received grant funding from the Singapore National Medical Research Council; a grant from the Department of Health and Social Care; the Foreign, Commonwealth, and Development Office; the Medical Research Council; and Wellcome Trust; as well as a grant from the UK Research and Innovation Medical Research Council. Dr. Dartois reported no relevant financial relationships. Dr. Chaisson had no disclosures to report.

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

A strategy for the treatment of tuberculosis involving just an 8-week treatment regimen – along with close posttreatment monitoring and treatment extension if needed – shows potential as an effective alternative to the standard 24-week regimen.

“We found that if we use the strategy of a bedaquiline-linezolid five-drug regimen for 8 weeks and then followed patients for 96 weeks, [the regimen] was noninferior, clinically, to the standard regimen in terms of the number of people alive, free of TB disease, and not on treatment,” said lead author Nicholas Paton, MD, of the National University of Singapore, in a press conference held during the Conference on Retroviruses & Opportunistic Infections.

“The total time on treatment was reduced by half – instead of 160 days, it was 85 days for the total duration.”

Commenting on the study, which was published concurrently in the New England Journal of Medicine, Richard E. Chaisson, MD, noted that, although more needs to be understood, the high number of responses is nevertheless encouraging.

“Clinicians will not feel comfortable with the short regimens at this point, but it is remarkable that so many patients did well with shorter treatments,” Dr. Chaisson, who is a professor of medicine, epidemiology, and international health and director of the Johns Hopkins University Center for Tuberculosis Research, Baltimore, said in an interview.

Importantly, the study should help push forward “future studies [that] will stratify patients according to their likelihood of responding to shorter treatments,” he said.

The current global standard for TB treatment, practiced for 4 decades, has been a 6-month rifampin-based regimen. Although the regimen performs well, curing more than 95% of cases in clinical trials, in real-world practice, the prolonged duration can be problematic, with issues of nonadherence and loss of patients to follow-up.

Previous research has shown that shorter regimens have potential, with some studies showing as many as 85% of patients cured with 3- and 4-month regimens, and some promising 2-month regimens showing efficacy specifically for those with smear-negative TB.

These efforts suggest that “the current 6-month regimen may lead to overtreatment in the majority of persons in order to prevent relapse in a minority of persons,” the authors asserted.
 

TRUNCATE-TB

To investigate a suitable shorter-term alternative, the authors conducted the phase 2-3, prospective, open-label TRUNCATE-TB trial, in which 674 patients with rifampin-susceptible pulmonary TB were enrolled at 18 sites in Asia and Africa.

The patients were randomly assigned to receive either the standard treatment regimen (rifampin and isoniazid for 24 weeks with pyrazinamide and ethambutol for the first 8 weeks; n = 181), or one of four novel five-drug regimens to be administered over 8 weeks, along with extended treatment for persistent clinical disease of up to 12 weeks, if needed, and a plan for retreatment in the case of relapse (n = 493).

Two of the regimens were dropped because of logistic criteria; the two remaining shorter-course groups included in the study involved either high-dose rifampin plus linezolid or bedaquiline plus linezolid, each combined with isoniazid, pyrazinamide, and ethambutol.

Of the patients, 62% were male, and four withdrew or were lost to follow-up by the end of the study at a final follow-up at week 96.

Among patients assigned to the 8-week regimens, 80% stopped at exactly 8 weeks, while 9% wound up having extended treatment to 10 weeks and 3% were extended to 12 weeks.

For the primary endpoint, a composite of death, ongoing treatment, or active disease at week 96, the rate was lowest in the standard 24-week therapy group, occurring in 7 of 181 patients (3.9%), compared with 21 of 184 patients (11.4%) in the rifampin plus linezolid group (adjusted difference, 7.4 percentage points, which did not meet noninferiority criterion), and 11 of 189 (5.8%) in the group in the bedaquiline plus linezolid group (adjusted difference, 0.8 percentage points, meeting noninferiority criterion).

The mean total duration of treatment through week 96 in the standard treatment group was 180 days versus 106 days in the rifampin–linezolid group, and 85 days in the bedaquiline-linezolid group.

The results were consistent across multiple subgroups defined according to baseline characteristics, including some that could be linked to severe disease and a high risk for relapse.

In terms of safety, there were no significant differences between the groups in terms of grade 3 or 4 adverse events.

Of note, only two patients (1.1%) in the bedaquiline plus linezolid group acquired a resistance, which Dr. Paton said was “encouraging,” because of concerns about resistance to that drug.
 

‘Unfavorable’ composite also evaluated

In an updated analysis of the study that Dr. Paton presented at the meeting, the authors looked at a revised “unfavorable” primary outcome – a composite including treatment failure, relapse, death, or nonattendance at week 96 without evidence of prior disease clearance.

The rate remained lowest in the standard 24-week therapy group (3.9%) versus 25% in the rifampin plus linezolid group, and 13.8% in the bedaquiline plus linezolid group.

Though the lower rate with the standard treatment was expected, Dr. Paton said the results nevertheless hold promise, at least for some patients, for successful treatment with the 8-week bedaquiline plus linezolid strategy.

“What the trial has told us is that even with that 13.8% relapse rate, we can manage patients within this strategy and people can do fine at the end, because with some simple clinical biomarkers, we can pick the people who may have a high chance of achieving a cure.”

Dr. Chaisson expressed concern over the higher unfavorable rates, but said the results help pave the way for refining a workable-shorter term strategy.

“TRUNCATE-TB did find that most patients could be successfully treated in 2 months with the novel regimen of bedaquiline plus linezolid, but the failure rate was still unacceptably high,” he said. 

“This regimen will not be widely adapted at this point, but additional analyses may identify subsets of patients who will do well with shorter regimens, and future studies will stratify patients according to their likelihood of responding to shorter treatments.”

The authors of an accompanying editorial further commented that the benefits of a shorter treatment strategy could very well outweigh possible shortcomings.

“Treatment algorithms such as that used in the TRUNCATE-TB trial are fundamental to tuberculosis control,” wrote Véronique Dartois, PhD, Center for Discovery and Innovation, Nutley, N.J., and Eric J. Rubin, MD, PhD, the editor-in-chief of NEJM. “Although implementing them could be a challenge, any added burden might be offset by reduced costs, better adherence, and increased patient satisfaction. Thus, for tuberculosis, a strategy might be more than just a regimen.”

The good news, as summed up by CROI vice-chair Landon Myer, MD, PhD, in the press conference, is that “we’re moving closer and closer to the holy grail of a short, efficacious regimen for TB treatment. We’re getting there slowly, but we’re getting there.”

The study received grant funding from the Singapore National Medical Research Council; a grant from the Department of Health and Social Care; the Foreign, Commonwealth, and Development Office; the Medical Research Council; and Wellcome Trust; as well as a grant from the UK Research and Innovation Medical Research Council. Dr. Dartois reported no relevant financial relationships. Dr. Chaisson had no disclosures to report.

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