New guidance from the Centers for Disease Control and Prevention (CDC) would recommend physicians prescribe a common antibiotic to help prevent the spread of sexually transmitted infections (STIs) in certain at-risk groups.
The CDC is proposing that health providers offer a single 200-milligram dose of doxycycline to gay and bisexual men who have sex with men, as well as transgender women, within 72 hours after having unprotected sex.
The agency published the draft Monday and opened a 45-day public comment window.
Studies have shown the so-called doxy PEP regime has led to a decrease in common STIs such as chlamydia, syphilis and gonorrhea. The agency said it could avert about 40 percent of STIs in affected populations.
The CDC said novel approaches are needed to address the STI epidemic, especially for populations disproportionately affected.
“Doxy PEP is moving STI prevention efforts into the 21st Century,” Jonathan Mermin, director of the CDC’s National Center for HIV, Viral Hepatitis, STD and TB Prevention, said in a statement. “We need game-changing innovations to turn the STI epidemic around, and this is a major step in the right direction.”
Record-high STIs threaten the health of millions of Americans. In the past decade, reported STIs have increased 42 percent from 2011 to 2021, with more than 2.5 million cases reported in 2021 alone, the CDC said.
The guidance is specific to the populations that would likely benefit the most — gay and bisexual men and transgender women who had an STI in the previous 12 months and were at high risk to get infected again.
It could also apply to people in that group who have not been diagnosed with an STI in the prior year but will be participating in sexual activities that are known to increase likelihood of exposure, such as festivals and cruises.
The CDC said focusing on the groups where data suggest the most substantial impact will maximize the impact of doxy PEP while minimizing antibiotic use overall.
The CDC guidelines were based on four studies of using doxycycline against bacterial STIs.
Doxycycline is a common and cheap antibiotic used to prevent infections such as malaria and Lyme disease. It is also the recommended treatment regimen for chlamydia and an alternative treatment for syphilis in nonpregnant patients with severe penicillin allergy or when penicillin is not available.
There haven’t been many studies on the effectiveness of doxy PEP among other groups, such as cisgender women, heterosexual men, transgender men or other queer and nonbinary individuals.
Doxy PEP should be effective in other populations based on experience treating other STIs, the agency said, but that research is an area of focus for the future.
The agency will also be monitoring the potential that widespread use of doxycycline could lead to other bacteria developing a resistance to it.
