WHO-recommended Periodic Presumptive Treatment versus Doxycycline Post-Exposure Prophylaxis for STI Control among Cisgender Men Who Have Sex with Men in Kenya

The Mambo Matatu Study

Start:                  September 2024

Status:                Awaiting start of recruitment

Design:               Clinical Trial

Study Sites:        Anza Mapema Centre of Excellence, PHDA Transform Clinic in Nairobi and Hapa Kenya Clinic in Mombasa

Sponsor:             National Institutes of Health  

IRB:                      KNH-UoN ERC

Purpose:             To conduct a propose a rigorous study to evaluate the impact and cost-effectiveness of WHO-recommended PPT versus doxyPEP among Kenyan MSM

Design:               The proposed study is an open-label randomized controlled trial with a hybrid type 1 implementation-effectiveness component comparing each intervention (i.e., STI PPT, doxyPEP) to a common control in a 2:2:1 ratio. Participants will undergo 18 months of follow-up at three MSM-friendly research clinics in Kenya. All cases of NG will be subject to rigorous culture-based and molecular analysis of AMR. The trial will have >80% power to detect a 33% reduction in a combined bacterial STI prevalence outcome, the optimal estimate of overall burden in a setting in which syndromic treatment is standard of care. We posit that there is equipoise to conduct a randomized trial, since while doxyPEP has demonstrated efficacy in studies of MSM in well-resourced settings in which NAAT-guided treatment are widely available, none of these studies was conducted in a resource-limited setting in which syndromic treatment is the norm. In addition, there have been no clinical trials of WHO-recommended STI PPT for MSM, which could have similar or greater efficacy, especially if doxycycline resistance in NG or poor adherence limit the efficacy of doxyPEP. Randomization in a 2:2:1 allocation with a common control arm will allow evaluation of both interventions in the same trial, and an open-label design allows for optimal evaluation of effectiveness and robust evaluation of acceptability, feasibility, and safety in practice, as well as adherence and sexual behaviour among participants who are aware of their assignment. 

Population:        Young MSM aged 18-29 living in Kisumu, Nairobi and Mombasa within the catchment areas of the three study sites will be eligible for recruitment into the study.

Study Size:          We will enrol 2900 MSM age 18-29 in this randomized controlled trial (1160 to each intervention arm and 580 in the control arm, with approximately 967 per site) and follow participants quarterly for 18 months..

Study Aims:        Aim 1. To evaluate the effectiveness and impact on AMR in NG of two interventions: WHO-recommended PPT given every 3 months and doxy-PEP taken 24-72 hours after condomless sex, compared to standard syndromic treatment, for reducing STI burden among Kenyan MSM.

Aim 2. To assess the acceptability, feasibility, and safety of implementing WHO-recommended PPT and doxy-PEP compared to standard care among providers and patients.

Aim 3. To model the health and economic impact of scaling up WHO-recommended STI PPT and doxyPEP compared to standard of care on STI control among MSM and their partners in Kenya.