As the United States grapples with a growing sexually transmitted disease crisis, a broad chorus of public health experts is urging the Centers for Disease Control and Prevention to support a preventive antibiotic pill for gay and bisexual men and transgender women at high risk of STDs. calling for. ,
But a growing body of research suggests that taking doxycycline after sex significantly lowers STD infection rates in this population — though not in cisgender women, according to the findings of a highly anticipated new study — which has some experts concerned that The widespread use of antibiotics on purpose may be doing more harm than good by fueling a global crisis of antibiotic-resistant infections and damaging people’s microbiomes.
“There’s going to be a very fierce debate about whether this is a good idea and for whom,” said Dr. Matthew Golden, director of the HIV and STD program at Seattle’s health department.
That debate has been at the forefront of the annual conference on retroviruses and opportunistic infections, which began in Seattle on Sunday, with new findings from several studies of doxycycline for STD prevention being revealed Monday.
This includes a third randomized trial in which gay and bi men (one of the previous trials also included trans women) were instructed to take an antibiotic within 72 hours after sex without a condom—a protocol known to be effective post-doxycycline. -Exposure Prophylaxis or known as DoxyPEP – reduces the risk of bacterial STDs. The new study, conducted in France, followed nearly 500 gay and bi men who received doxyPEP or no antibiotic and found that doxycycline reduced rates of gonorrhea, chlamydia, and syphilis by 51% to 89%.
Another study found that there was no significant increase in doxycycline resistance among the three major bacteria, including gonorrhea and staph, in the other DoxyPEP trials. However, this is unlikely to settle the ongoing debate on the matter.
Less controversial among public health experts is the potential for using a vaccine for STD prevention. The French study further found that a meningococcal B vaccine cut new gonorrhea infections in half.
The Seattle conference also looked at findings from a randomized study of cisgender women in Kenya that found that DoxyPEP had no effect on their STD rates. Calling the study’s results “very disappointing”, its director, Dr. Janelle Stewart, an infectious disease physician at the University of Minnesota, said differences in anatomy, antibiotic resistance and adherence to drug protocols could at least partially explain the lack of efficacy. While in women, DoxyPEP has consistently worked well in gay men in Western countries.
New efficacy research shared Monday builds on previously released findings that in recent years have fueled growing excitement within the infectious disease field over the promise of doxycycline as the answer to out-of-control STD transmission.
One study, conducted in Seattle and San Francisco and presented at a July conference, found a two-thirds overall reduction in STDs among gay and bi men and trans women. A previous French study published in 2017 found that the intervention dramatically reduced syphilis and chlamydia infections, but did not affect gonorrhea.
“The data show a consistent benefit in men in terms of reducing the incidence of bacterial STIs,” said Dr. Jean-Michel Molina, lead author of the French studies and LGBTQ health researcher at Université Paris City. , referring to the term sexually transmitted infection. He added that more research is needed to confirm the vaccine’s efficacy for gonorrhea.
Paul Marcellin, a 48-year-old software engineer living in Alameda, California, participated in the Seattle-San Francisco study and was assigned to a control group that did not receive antibiotics. They were offered DoxyPEP last summer, after the study was discontinued early due to high efficacy.
Marceline said of her experience taking doxycycline for prevention, “It’s been very positive, as an additional source of peace of mind, considering she usually only contracts an STD once every two years.” does and hasn’t had any since starting DoxyPEP.”It’s part of my health routine.”
Gay and bi men, as well as transgender women, have been the focus of much recent research into the pharmacological prevention of STDs, as they have higher rates of such infections than cisgender heterosexual people (homosexuals, meanwhile, have a higher rate of infection than heterosexual people). comparatively low rate). Men who have sex with men, for example, comprise less than 2% of the US adult population, but account for more than 40% of US syphilis diagnoses, according to the CDC.
Over the past two decades, gonorrhea, chlamydia and syphilis have increased to 2.5 million cases in 2021. The CDC estimates that it saddled the nation with $1.1 billion in direct medical costs.
Most critically, syphilis—a scourge that was nearly eradicated in the late 1990s but the CDC reports is set to skyrocket 68% between 2017 and 2021, to 171,000 cases—for infants born to uncircumcised women. There is a potentially fatal hazard. In rare cases, it can also damage vision or cause blindness.
David Harvey, executive director of the National Coalition of STD Directors, said federal cuts to state STD programs have led to overall infection growth.
Condom use, especially among gay and bisexual men, has seen a long decline since HIV became treatable, and thus less frightening, in 1996, and a decade ago with the advent of the HIV preventive pill. With what is known as PrEP.
Harvey, like many other public health experts, is looking to doxycycline, which typically costs pennies per pill, as a powerful tool that could help turn the STD tide.
DoxyPEP concerns
However, some infectious disease experts are deeply concerned that the adoption of DoxyPEP may encourage the emergence of drug-resistant pathogens, particularly staph.
“Overall, my biggest fear is that they are not thinking about global antimicrobial resistance,” said Fabian Kong of the University of Melbourne, a champion of doxyPEP. “They’re just thinking about the STI world.”
The World Health Organization lists antimicrobial resistance as one of the top 10 global public health threats facing humanity.
Approved in the 1960s, doxycycline is widely prescribed to treat acne and rosacea, to treat or prevent Lyme disease, and to prevent malaria among travelers and the military. Other tetracyclines, the antibiotic class to which doxycycline belongs, have long been used in livestock production — much to the concern of many infectious disease experts, who worry that it fuels drug-resistant infections that could affect humans.
For DoxyPEP, such concern is probably less relevant than for the three major STDs. There is no evidence that chlamydia has acquired resistance to tetracycline and there is only little evidence for syphilis. Additionally, the drug class is not used to treat gonorrhea. However, some experts believe it is possible that the use of DoxyPEP could enhance existing resistance in the gonorrhea strain, potentially making the intervention’s ability to prevent that STD short-term.
But by reducing the spread of STDs, some experts argue, DoxyPEP could lead to less antibiotic use to treat such infections and less spread, potentially reducing the emergence of drug-resistant strains.
The CDC has issued increasingly urgent warnings in recent years about the ability of gonorrhea to evade the last remaining simple and effective antibiotic treatment for the infection.
Dr. Annie Luetkemeyer, a professor of medicine at the University of California, San Francisco, presented findings at the Retrovirus Conference about a subset of the 637 participants in the Seattle-San Francisco study. The researchers did not find a significant increase in doxycycline resistance for three of those bacteria: Neisseria gonorrhoeae, Staphylococcus aureus and non-pathogenic Neisseria. These findings are limited by the fact that participants were not followed for more than a year, did not have many gonorrhea samples to test, and few in the control group received doxycycline to treat an STD.
“I don’t think any resistance findings are a showstopper for DoxyPEP yet,” Luetkemeyer said. “However, we will need to thoughtfully monitor for STIs and resistance in off-target bacteria such as Staph aureus to understand the effect of DoxyPEP over time.”
Luetkemeyer and colleagues also found that people who were given DoxyPEP received the standard antibiotic treatment for gonorrhea, ceftriaxone, with 50% fewer infections.
Kong and other experts are also concerned about the effects of regular doxycycline on people’s microbiomes. Luetkemeyer said it’s a challenging question to answer, and one that he and his colleagues continue to study along with the antimicrobial resistance concern.
The Future of DoxyPEP
Drug resistance and microbiome concerns notwithstanding, some infectious disease experts say the time has come for the CDC to support the rollout of DoxyPEP among some gay men and trans women.
Dr. Jeffrey Klausner is an infectious disease specialist at the University of Southern California and author of several papers on doxycycline as an STD prevention. Proposing to provide DoxyPEP only to those at risk of STDs, he said, “It’s really a drop in the ocean of tetracycline use, but it could have substantial benefits on sexually transmitted infections.”
A 2018 study found that over a two-year period, only 0.1% of people aged 13 to 65 in Massachusetts had more than one STD, and this small group of only 7,000 people The state accounted for 28% of all STDs during this time period.
Michael Traeger, a research fellow at Harvard Medical School, presented a modeling study at the Seattle conference in which he and his colleagues reviewed patient data at Fenway Health, an LGBTQ-focused clinic in Boston, and identified what they could at least do. What characterizes an efficient set strategy? Antibiotic use while maximizing effectiveness: Give DoxyPEP for 12 months to gay and bisexual men with a recent STD. This, they estimated, could prevent up to 42% of subsequent STDs in the overall patient population.
Even in the absence of formal CDC guidance, some gay men are already taking doxycycline for STD prevention. And in October, the San Francisco Department of Public Health became the first in the nation to establish interim DoxyPEP guidelines. Additionally, some LGBTQ-focused clinics, including Howard Browne Health in Chicago and the Los Angeles LGBT Center, have recently adopted, or will soon adopt, such protocols.
“We should not confuse antibiotic prophylaxis with antibiotic abuse,” said Dr. Anu Hazra, a physician at Howard Browne who has been involved in the public health field since helping the CDC establish the DoxyPEP guidelines. “We treat antibiotic prophylaxis for many different diseases and conditions. use antibiotics as prophylaxis for AD where the data support its use.”
According to Dr. Leandro Mena, the CDC’s director of STD prevention, the agency has begun laying the groundwork to potentially establish DoxyPEP guidelines. He said that once the Seattle-San Francisco study is published, possibly by spring, the effort will move forward and include a review of the relevant science as well as expert and community input — potentially a months-long process.
“We know it works,” Mena said of DoxyPEP. She added that the CDC is concerned with assessing the safety of interventions, “which populations may benefit most” and addressing equity concerns, noting that people of color contract STDs disproportionately.
