This is an unexpected solution but applauded by medical professionals. In the coming weeks, the main US federal health agency comprising the Centers for Disease Control and Prevention (CDC) is to set out new recommendations regarding the prevention of sexually transmitted infections (STIs).
Long-awaited announcements, while some of these STIs are responsible for epidemics affecting millions of Americans. But beyond the usual prevention tools, the authority of the CDC plans to add a new weapon to its arsenal: doxycycline, an antibiotic developed decades ago and transformed into a preventive pill.
A reduction of infections between 55 and 80%
As the American media explains CNN, doxycycline is a type of drug “traditionally used to treat bacterial STIs after a person has been infected”. However, according to this media and AFP, several recent clinical trials demonstrate that a dose of 200 mg of doxycycline taken within 72 hours after sexual intercourse without a condom would significantly reduce the risk of infection with three diseases: chlamydia, gonorrhea and syphilis.
The new approach, called “DoxyPEP,” is being touted as “the first major STI intervention we’ve had since the human papillomavirus vaccine” by CDC director for HIV prevention Jonathan Mermin. cited by the washington post.
Doxycycline has been shown to be effective in three of the four clinical trials conducted, indicating “a two-thirds reduction in sexually transmitted infections,” American researcher Annie Luetkemeyer, who conducted one of these trials, told AFP. Efficacy was even found to be higher against chlamydia and syphilis, reducing the number of infections by 80%, while taking DoxyPEP reduced gonorrhea infection by 55%. Trials with few side effects, carried out on patients from the most at-risk social groups: gay and bisexual men, as well as transgender women with previous infections.
A solution already on the black market
If this announcement delights the CDC so much, it is because the United States has counted for a decade an explosion of cases of bacterial infections concerned by doxycycline, reaching 2.5 million people infected in 2021. “The number of cases of syphilis in the United States is at its highest level for more than 50 years. The nation needs new tools to prevent STIs”, alerts Jonathan Mermin to CNN. If more infections automatically increase the number of transmissions, this explosion is also linked to a lower use of condoms among populations at risk due to the democratization of PrEP, a drug taken before intercourse to avoid contracting the HIV virus. AIDS.
But according to Stephen Abbott, a doctor in Washington who prescribes and uses doxycycline, it is crucial to take into account changes in behavior. Taking PrEP himself, he even judges that “the era of prevention via condoms is in decline”. Like him, some doctors already prescribe the antibiotic for this purpose. AFP cites the example of Malik, a 37-year-old resident of Washington, who has already used DoxyPEP twice on the advice of his doctor. Similarly, this new treatment can already be bought on the black market, according to the anonymous testimony of an official of a cultural organization in London.
A tool criticized by some doctors
However, the CDC’s announcement of wanting to extend access to doxycycline has also triggered concerns among some doctors: resistance to antibiotics could indeed develop, in particular for gonorrhea, whose bacteria mutate rapidly. The CDC will therefore have to respond to the fears of professionals in its recommendations for taking DoxyPEP.
THE first analyzes of an American clinic, however, seem nuanced. Because if they show a slight increase in antibacterial resistance after using DoxyPEP, notes the washington post, they do not directly prove cause and effect. In addition, the use of doxycycline can halve the number of people affected, taking the antibiotic prescribed against gonorrhea would also prove to be less necessary.
Researcher Annie Luetkemeyer also points out to AFP that doxycycline cannot be the only answer to STD epidemics. She sees in this old antibiotic “an additional tool”, in particular pending the development of a vaccine against gonorrhea.