Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Jan 30:ciaf043.
doi: 10.1093/cid/ciaf043. Online ahead of print.

A pilot, randomized controlled trial of Dual Daily HIV and sexually transmitted infection pre-exposure prophylaxis using tenofovir disoproxil fumarate/emtricitabine and doxycycline in gay, bisexual and other men who have sex with men and transgender women: The DuDHS Study

Affiliations

A pilot, randomized controlled trial of Dual Daily HIV and sexually transmitted infection pre-exposure prophylaxis using tenofovir disoproxil fumarate/emtricitabine and doxycycline in gay, bisexual and other men who have sex with men and transgender women: The DuDHS Study

Troy Grennan et al. Clin Infect Dis. .

Abstract

Background: Men who have sex with men (MSM) and transgender women experience high sexually transmitted infection (STI) rates. This study evaluated the feasibility of doxycycline pre-exposure prophylaxis (doxyPrEP) for STI prevention in these key populations.

Methods: Sexually-active MSM and transgender women without HIV with prior syphilis were recruited. Participants initiated HIV PrEP with tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) daily for 48 weeks, and were randomized 1:1 to daily doxyPrEP for 48 weeks (immediate arm), or doxyPrEP initiated at 24 weeks (deferred arm). Primary outcomes included adherence, measured using questionnaires, along with tolerability; STI incidence (chlamydia, gonorrhea, syphilis) was a secondary outcome. Nasal carriage of S. aureus was assessed serially for doxycycline resistance.

Results: Fifty-two participants were enrolled into the immediate (n=26) and deferred (n=26) arms. At 48 weeks, self-reported adherence (≥95%) was 75.0% vs. 66.7% (p=0.538) for TDF/FTC, and 70.8% vs. 61.9% (p=0.526) for doxycycline in the immediate vs. deferred arms, respectively. No doxyPrEP-related serious adverse events occurred. Incidence of any STI at 24 weeks was reduced in the immediate vs. deferred arms, and over 48 weeks, being on doxycycline (vs. being off; i.e. first 24 weeks of deferred arm) was associated with STI reduction (adjusted odds ratio [aOR] 0.36; 95 % confidence interval [CI] 0.15-0.89). Emergent doxycycline-resistant S. aureus was identified in six individuals, with five in the immediate arm (p=0.077).

Conclusions: Dual HIV/doxyPrEP is feasible and associated with a significant reduction in incident STI. Further evaluation of dosing strategies, efficacy and impact on antimicrobial resistance is warranted.

Keywords: STI prevention; doxyPrEP; doxycycline; men who have sex with men (MSM); sexually transmitted infections (STI); transgender women.

PubMed Disclaimer

LinkOut - more resources