Nevertheless, the study also found a slight increase in antibacterial resistance, which warrants further investigation, the authors found.
Experts say there is a great need for effective methods to prevent sexually transmitted infections. This is an encouraging finding that may help reduce the number of sexually transmitted infections in populations most at risk.
The rise of STIs
The incidence of sexually transmitted infections has been on the rise in the United States over the past few years, and it disproportionately affects gay men and transgender women.
According to the Centers for Disease Control and Prevention, an estimated 2.5 million cases of syphilis, gonorrhea, and chlamydia occurred in 2021, up from 2.4 million cases in 2020. If left untreated, STDs can lead to serious health consequences, including brain and nerve problems, blindness, infertility, and an increased risk of HIV infection. Among STIs, antimicrobial resistance is a particularly emerging public health threat Neisseria gonorrhoeaeand threatens existing treatment options.
About research
The study included 501 adults at least 18 years old at four clinics in San Francisco and Seattle; assigned male gender at birth; reported having sex with a man in the previous year; When diagnosed with HIV or taking or planning to take pre-exposure prophylaxis (PrEP) medication to prevent HIV infection; and diagnosed with gonorrhea, chlamydia, or early syphilis in the previous year. Of those enrolled, 327 participants were taking HIV PrEP medication, and 174 participants were people living with HIV.
Participants were randomly assigned to receive either doxy-PEP or standard care. Those in the doxy-PEP arm were instructed to take a 200-mg (mg) delayed-release tablet of doxycycline, ideally within 24 hours but no later than 72 hours after unprotected intercourse.
Doxycycline is a broad-spectrum antibiotic belonging to the tetracycline group. Participants were assessed by study staff every three months for adherence to the medication regimen and side effects and tested for STDs. Participant adherence to medication was assessed at the six- and 12-month clinic visits. An independent data and safety monitoring board reviewed study progress and safety and efficacy data every six months.
How doxycycline affects STIs
Among HIV PrEP participants, at least one or more STDs were diagnosed in 10.7% of quarterly clinic visits in the Doxy-PEP study group, compared to 31.9% in the standard care group.
Among study participants living with HIV, one or more STDs were diagnosed in 11.8% of quarterly visits in the doxy-PEP unit versus 30.5% in the standard care group.
Gonorrhea was the most commonly diagnosed STI in the study. Participants reported good adherence to the medication regimen, with 86.2% taking doxy-PEP consistently within 72 hours of unprotected intercourse and 71.3% never missing a dose. No safety or acceptability issues were identified in the study.
Consider Doxy-PEP for Men’s Sexual Health
“Given its demonstrated efficacy in several trials, doxy-PEP should be considered as part of a sexual health package if men who have sex with men and women who have sexually transmitted infections are at increased risk for STIs,” said Annie Luetkemeyer, MD, MD. Zuckerberg is a principal investigator in infectious disease and research at San Francisco General Hospital at UCSF.
“It will be important to monitor the effect of doxy-PEP on antimicrobial resistance patterns over time and to compare this with the demonstrated benefit of reducing STIs in men at high risk of recurrent STIs and the associated reduction in antibiotic use for STI treatment.”
Doxy-PEP may not be effective against gonorrhea
When examining the potential for antimicrobial resistance during doxy-PEP use, researchers found tetracycline resistance in gonorrhea strains more common among those in the doxy-PEP arm than among those in the standard care group (38.5% vs. 12.5%). according to %).
This suggests that doxy-PEP may offer less protection against gonorrhea strains that are already resistant to tetracyclines, and that broader population-based surveillance for this type of resistance is important.
Doxy-PEP Also Reduces Staphylococcus Skin Infections
In addition, the researchers found that doxy-PEP decreased Staphylococcus aureus– skin “colonization” bacteria – 50% after one year.
However, among those still colonized with Staphylococcus aureus at month 12, a modestly higher proportion of those in the doxy-PEP group had doxycycline resistance (16% vs. 8%). This is important because doxycycline can be used to treat resistance to methicillin Staphylococcus aureus skin and soft tissue infections.
Further research and longer follow-up periods are needed to investigate the potential antimicrobial resistance effect of intermittent doxy-PEP use. The use of Doxy-PEP in other populations disproportionately affected by STIs, including HIV-infected women and those taking HIV PrEP, also deserves further investigation.
“We need new, effective STI prevention methods, and three studies have now shown that doxy-PEP significantly reduces gonorrhea, chlamydia, and syphilis. As we roll out doxy-PEP over the next few years, we hope to maximize equitable access and impact.” we need to learn,” said Dr. Connie Celum said.
Reference:
- After contact with Doxycycline to prevent bacterial sexually transmitted infections – (https:www.nejm.org/doi/10.1056/NEJMoa2211934)
Source: Medium