Background
Digital Health intervention is promising for encouraging behavior change. We conducted a stepped-wedge trial (SWT) to evaluate the efficacy of co-created digital PrEP adherence intervention to facilitate adherence among Chinese MSM PrEP users.
Methods
This trial is nested in a PrEP demonstration trial in Guangzhou and Wuhan, China (NCT04754139). Participants were provided TDF/FTC for 12 months and followed up quarterly (M3, M6, M9, M12). MSM were randomly allocated to four sequential groups receiving weekly WeChat-based (a popular Chinese chat media) digital messages in a quarterly staggered order. Intervention messages were co-created through open calls and three co-creation rounds with 19 PrEP users in the trial, including short videos, images, and infographics. Per-protocol analysis and generalized linear mixed-effects models were used to assess primary outcomes, including self-reported optimal PrEP adherence in past 30 days (daily users: 6-7 pills/week, on-demand users: full compliance with the 2-1-1 dosing scheme per sex event) and study retention (i.e. whether loss to follow-up).
Results
From July 2021 to September 2024, 1087 MSM (mean age=28.0, IQR=24.0-31.4) enrolled. About one quarter of participants were college students, and three quarters had 2 or more sex partners in the past 3 months. About half of the participants reported using on-demand regimen (2:1:1) throughout the study. Participants enrolled in each SWT cluster at baseline were 251, 281, 276, and 279, respectively. About 33.8% (n=368) of the participants dropped out or lost to follow-up before M12, with no significant difference across SWT clusters. From M3 to M12, over 75% of the participants reported optimal adherence to PrEP, with a non-significant secular trend of declining adherence over time. The digital intervention marginally improved adherence levels (aOR=1.18, 95%C.I.: 0.85-1.60), but not statistically significant. On-demand PrEP users versus daily PrEP users were less likely to report optimal adherence (aOR=0.06, 95%C.I.: 0.04-0.09). MSM with higher income or having less sex partners are more likely to report optimal adherence.
Conclusions
Digital PrEP adherence intervention messages with Chinese MSM has the potential to improve self-reported adherence. Our findings of varied adherence performance among individuals highlight the need for future research into differentiated PrEP interventions.