Doxycycline for preventing bacterial STIs in men who have sex with men

A Randomized Trial of Doxycycline Chemoprophylaxis for the Prevention of Sexually Transmitted Infections in Gay, Bisexual and Other Men Who Have Sex With Men (gbMSM)

This study tests if taking doxycycline every day or just after potential exposure can help prevent bacterial STIs in gay, bisexual, and other men who have sex with men.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 560 (estimated)
• Ages: 18 Years and up
• Sex: Male
• Sponsor: British Columbia Centre for Disease Control (Government)
• Locations: 6 sites (Calgary, Alberta and 5 other locations)
• Trial ID: NCT04762134 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates the effectiveness of doxycycline as a preventive measure against bacterial sexually transmitted infections (STIs) in gay, bisexual, and other men who have sex with men (gbMSM). It compares two approaches: daily doxycycline as pre-exposure prophylaxis (PrEP) and a single dose after potential exposure as post-exposure prophylaxis (PEP). The study will follow participants for 15 months to assess the efficacy, safety, and adherence to the treatment, while also evaluating the potential for antimicrobial resistance. This rigorous randomized controlled trial aims to provide healthcare providers with a new tool to combat the rising rates of bacterial STIs in this high-risk population.

Who should consider this trial

Good fit: Ideal candidates include males aged 18 and older who have had sexual activity with multiple male partners and a history of bacterial STIs.

Not a fit: Patients who are allergic to doxycycline or currently using medications that interact with doxycycline may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could significantly reduce the incidence of bacterial STIs among gbMSM, improving overall sexual health outcomes.

How similar studies have performed: Other studies have shown promise in using doxycycline for STI prevention, making this approach both relevant and potentially impactful.

Eligibility criteria

Inclusion Criteria:

1. Males, ≥ 18 years of age;
2. Any sexual activity (i.e. oral sex, insertive or receptive anal sex, with or without a condom) with more than one male partner in the preceding 12 months;
3. Intention to remain sexually active with more than one male partner in the next 12 months;
4. At least one prior episode of a previously diagnosed and adequately treated syphilis, gonorrhea or chlamydia infection within 12 months prior to screening.

Exclusion Criteria:

1. Known allergy to doxycycline or tetracyclines;
2. Existing chronic or intermittent tetracycline or doxycycline use (e.g. for chronic osteomyelitis, acne).
3. Use of medications which could lower doxycycline levels, including barbiturates, phenytoin and carbamazepine.
4. Individuals currently using isotretinoin;
5. Any individual capable of becoming pregnant.

Where this trial is running

Calgary, Alberta and 5 other locations

• Sheldon Chumir Centre — Calgary, Alberta, Canada (Recruiting)
• BC Centre for Disease Control — Vancouver, British Columbia, Canada (Recruiting)
• St. Joseph's Healthcare Hamilton — Hamilton, Ontario, Canada (Not_yet_recruiting)
• The Ottawa Hospital — Ottawa, Ontario, Canada (Not_yet_recruiting)
• St. Michael's Hospital — Toronto, Ontario, Canada (Recruiting)
• McGill University Health Centre — Montreal, Quebec, Canada (Recruiting)

Study contacts

• Principal investigator: Troy Grennan, MD — University of British Columbia
• Study coordinator: Saira Mohammed

Conditions Bacterial Sexually Transmitted Diseases; Sexually transmitted infections; Doxycycline; Pre-exposure prophylaxis; Post-exposure prophylaxis; Gay, bisexual, men who have sex with other men