DOXYCYCLINE MONOHYDRATE for Bacterial sexually transmitted infections

Inclusion criteria

• {"criterion_text":"- Able and willing to provide informed consent and adhere to the study procedures\n- Aged 18 years or older\n- Assigned male sex at birth\n- Identifying as gay, bisexual or other men who have sex with men or transgender women\n- Living with HIV\n- Having an undetectable viral load (<200 copies/mL) for 6 months or more\n- Having had at least one bacterial sexually transmitted infection in the preceding 24 months or having had >= 5 sex partners in the previous 6 months"}

Exclusion criteria

• {"criterion_text":"- Hypersensitivity to doxycycline or other tetracyclines, any substance used in the IMP or placebo, or any of the excipients listed in section 6.1 of the SmPC.\n- Concomitant use of medication with significant interactions with doxycycline\n- Any contra-indication to the use of doxycycline, as mentioned in the summary of product characteristics"}

Primary endpoints

• {"endpoint_text":"- Incidence rate ratio of symptomatic NG, CT, and all TP infections in the doxyPEP vs placebo arms","definition_or_measurement_approach":"Incidence rate ratio comparing the incidence of symptomatic Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) and all Treponema pallidum (TP) infections between doxyPEP and placebo arms."}

Secondary endpoints

• {"endpoint_text":"- Rate ratio of tetracyclines, macrolides, cephalosporins, and penicillins in the doxyPEP vs placebo arms\n- MIC distribution (doxycycline/cefixime/ciprofloxacin) of commensal Neisseria spp. and E. coli in the doxyPEP vs placebo arms\n- Microbiota diversity, microbiota richness, abundance and diversity of Bifidobacteria, Fusobacterium, Lactobacillaceae, Enterobacteriaceae and Bacteroidaceae in both arms. Abundance of resistance genes (tetracyclines and other classes of antimicrobials) in both arms\n- Incidence rate ratio of symptomatic NG infections in the doxyPEP vs placebo arms\n- Incidence rate ratio of symptomatic CT infections in the doxyPEP vs placebo arms\n- Incidence rate ratio of symptomatic TP infections in the doxyPEP vs placebo arms\n- Incidence rate ratio of all NG infections in the doxyPEP vs placebo arms\n- Incidence rate ratio of all CT infections in the doxyPEP vs placebo arms\n- Incidence rate ratio of all TP infections in the doxyPEP vs placebo arms\n- Tetracycline MIC distribution of NG isolates in the doxyPEP vs placebo arms","definition_or_measurement_approach":"Comparative analyses between doxyPEP and placebo arms: antibiotic consumption rate ratios; MIC distributions for specified antimicrobials in commensal Neisseria spp. and E. coli; microbiota diversity and abundance metrics and resistome profiling; incidence rate ratios for symptomatic and all infections by pathogen; tetracycline MIC distribution among NG isolates."}

Methods

• Posters and flyers in English/French/Dutch (documents L_2025-521153-16-00_flyer_EN/FR/NL and poster_EN/FR/NL) aimed at MSM and transgender women living with HIV in Belgium; Site-based recruitment at participating clinics (Institute Of Tropical Medicine, CHU Saint Pierre); subject information and informed consent forms provided (multiple language versions).
• Recruitment arrangements documented (document K_2025-521153-16-00_informedconsent_patientrecruitmentprocedure).

Belgium

Earliest CTIS Part Ii Submission Date

16-05-2025

Latest Decision Or Authorization Date

02-06-2025

Processing Time Days

17

Number Of Sites

2

Number Of Participants

200

Primary sponsor

Full Name

Institute Of Tropical Medicine

Organisation Type

Hospital/Clinic/Other health care facility

Country Of Registered Address

Belgium