Superiority of On-demand PrEP Versus PEP on Using Doxycycline for Preventing STI in MSM

• Status: Not yet recruiting
• Trial end date: 2027-03-01
• Target enrollment: 0
• Participant gender: Male

Summary

The goal of this clinical trial is to compare the effectiveness of doxycycline taken for on-demand pre-exposure prophylaxis (DoxyODPrEP) and its post-exposure use (DoxyPEP) in preventing bacterial sexually transmitted infections (STI), including chlamydia, gonorrhoea, and syphilis among men who have sex with men (MSM). The main questions it aims to answer are:

1. Is DoxyODPrEP superior to DoxyPEP?

2. Are both regimens safe?

3. Does the MSM community accept the use of doxycycline to prevent bacterial STI?

Participants will be asked to take doxycycline according to the study arm they are randomly assigned to, and attend regular clinical follow-ups during the 2-year observation period. Researchers will compare the bacterial STI incidences between the two groups to see if DoxyODPrEP is superior to DoxyPEP.

• Phase: Phase 4
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: Chinese University of Hong Kong
• Treatments: Doxycycline

Criteria

Inclusion Criteria:

• has had sex with another male in the past six months

• normally reside in Hong Kong

• can communicate in written and spoken Chinese or English

• willing and able to give written informed consent

• being willing and able to attend scheduled study clinic visits

• at risk of STI (had condomless sex with more than one man in the past 12 months, history of STI diagnosis in the past 12 months, inclination to have condomless sex, and other HIV-PrEP-eligible criteria)

Exclusion Criteria:

• Being allergic to tetracycline class medicines

• Currently taking medications that are contraindicated with doxycycline

• Using antibiotics for more than 14 days in the month preceding enrolment