Doxycycline Prophylaxis for Bacterial Sexually Transmitted Infections

Abstract

<jats:title>Abstract</jats:title> <jats:p>Bacterial sexually transmitted infections (STIs) have been increasing over the past 2 decades in gay, bisexual, and other men who have sex with men. With the widespread use of early human immunodeficiency virus (HIV) treatment, which virtually eliminates transmission risk, and the availability of HIV pre-exposure prophylaxis, there have been attitudinal changes regarding HIV infection with resultant increases in sexual contact and declines in condom use. Doxycycline is used for primary prophylaxis in a number of infectious diseases. We conducted a state-of-the-art review to examine the current state of research, knowledge gaps, and challenges around the use of doxycycline prophylaxis to prevent syphilis and other STIs. International academic and government experts met in March 2019 to frame the initial inquiry, which was supplemented by focused literature searches. Two small short-term randomized controlled trials examining doxycycline prophylaxis found high efficacy. Five additional clinical studies are underway or in development. Studies differed in design, population, outcomes, and safety measures. Doxycycline prophylaxis for bacterial STIs shows promise. Better and more robust data are needed on efficacy; target population; community acceptability; behavioral risk compensation; doxycycline dose, regimen, and formulation; long-term safety; antimicrobial resistance; cost-effectiveness; and risk–benefit.</jats:p>

2020 European guideline on the management of syphilis

“…Although this has been shown to potentially decrease the incidence of syphilis and chlamydia, follow‐up has been short and there is a risk of promoting development or acquisition of tetracycline resistance in STI bacteria and the microbiome more generally. Additional studies in different settings and with longer follow‐up are required before this prophylactic treatment can be recommended 144 …”

“…Partner notification may have to be extended to 2 years for patients with secondary syphilis associated with clinical relapse or in early latent syphilis. Longer time periods may be required in those with late latent and tertiary syphilis 144 46–60% of traced sexual contacts, including pregnant women, of patients with early syphilis are likely to be infected 146 …”

Factors associated with reporting antibiotic use as STI prophylaxis among HIV PrEP users: findings from a cross-sectional online community survey, May–July 2019, UK

“…In the same way that antiretroviral therapy is used to prevent HIV infection in the forms of PrEP and post-exposure prophylaxis (PEP), there is evidence that antibiotics for STI treatment could be used to prevent STIs. Doxycycline is a tetracycline antibiotic, which is commonly used as primary prevention (pre-and post-exposure prophylaxis) for several infectious diseases (4) and bacterial STIs treatment, but more recently has been assessed by studies as a preventative intervention for STIs (5). A sub-study of the ANRS-IPERGAY trial in France among 232 high risk men who have sex with men (MSM) using HIV PrEP, showed that Doxycycline post-exposure prophylaxis (Doxy-PEP) following condomless sex, was effective in reducing incidence of a first episode of chlamydia and syphilis but not gonorrhoea (6).…”

The burden of HIV, syphilis and schistosome infection and associated factors among adults in the fishing communities in northwestern Tanzania

“…Daily doxycycline would also have the benefit of treating latent syphilis given its status as a second‐line agent against T. pallidum [25]. Multiple trials are currently ongoing to assess the utility of doxycycline prophylaxis among high‐risk populations such as men who have sex with men [26]. Our data further identify fishing communities as another important target group to consider for such interventional studies.…”