A latent trajectory analysis of young sexual and gender minorities’ adherence to three rectal microbicide placebo formulations (MTN-035; a randomized crossover trial)
Authors: Choi Seul Ki , Bauermeister José , Tingler Ryan C. , Johnson Sherri , Macagna Nicole , Ho Ken , Hoesley Craig , Liu Albert , Kayange Noel , Palanee-Phillips Thesla , Chariyalertsak Suwat , Gonzales Pedro , Piper Jeanna M. ,   MTN-035 Protocol Team, Mnemba Abigail , Kamanga Alinafe , Munthali Annie , Gondwe Daniel , Seyama Linly , Mbilizi Yamikani , Chadza Mary , Mayani Josiah , Rees Helen , Moodley Kerushini , Reddy Krishnaveni , Twala Andile , Jacques Ashleigh , Nyamuzihwa Tsitsi , Cassim Nazneen , Miranda Ana , Morales Diana , Chapa Helen , Valencia Javier , Sabaduche Milagros , Pareja Karina , Milagros Katherine , Macassi Charri , Saokhieo Pongpun , Manoyos Veruree , Kosachunhanan Nataporn , Sroysuwan Piyathida , Matthews Allison , Player Amy , Thurman Andrea , Mitchell Carol , O’Neill Christine , Pappalardo Christy , Quan Christopher , Jacobson Cindy , Yip Clifford , Hoesley Craig , Camp Danielle , Powell Deon , Singh Devika , Ng Diana , Livant Edward , Brown Elizabeth , Helms Emily , Schaeffer Emily , Heard Faye , Brown Gina , Doncel Gustavo , Gundacker Holly , Scott Hyman , Fitzpatrick Jackie , Gavel James , Weber Jenna , Schille Jennifer , Webster Jessica , Maitz Jessica , Zemanek Jillian , Pickett Jim , Lucas Jonathan , Nowak Julie , Dietz Kathleen , Welch Krissa , Heath Kristine , Rohan Lisa , Lacanlale Lizardo , Mitterer Lynn , Richards Lorna , Bolton Marcus , Song Mei , Cleland Naana , Ng Nicholas , Okey-Igwe Nnennaya , Singh Onkar , Peters Patricia , Giguere Rebecca , Weinman Renee , Black Roberta , Fields Scott , Riddler Sharon , Hillier Sharon , Karas Sherri , Edick Stacey , Dadabhai Sufia , Buchbinder Susan , Taha Taha , Billups Tarana , Senn Teri , Wagner Theresa , McCormick Tim , Jiao Yuqing 
Published: December 2023

Abstract
Background
Rectal microbicides (RM) are biomedical HIV prevention products that aim to prevent or reduce the transmission of HIV and other sexually transmitted infections (STIs). RM modalities may be beneficial for populations who have complex lifestyles, difficulties adhering to pre-exposure prophylaxis (PrEP) regimens, and/or have limited access to care. MTN-035 (DESIRE; Developing and Evaluating Short-Acting Innovations for Rectal Use), a randomized crossover trial, aimed to evaluate the safety and acceptability of, and adherence to, three placebo RM modalities (douche, insert, and suppository) prior to receptive anal intercourse.

Methods
We conducted latent trajectory analysis to identify clusters of individuals who shared similar trajectories in acceptability and adherence for each product (douche, insert, and suppository) over time. We analyzed weekly short messaging service (SMS) use reports for each modality as reported by enrolled sexual and gender minority (SGM) participants.

Results
Two trajectories for each product were identified: a “protocol compliant” trajectory (i.e., at least one product use occasion per week) and “high use” trajectory (i.e., more than three product use occasions per week). Participants with high use were more likely to lack access to PrEP and have higher intentions to utilize RM modalities compared to those who were protocol compliant.

Conclusions
This study highlighted high adherence to RM modalities among SGM. As research into viable HIV prevention modalities continues to evolve, tailored intervention strategies are needed to support the uptake of and adherence to alternative prevention modalities that are behaviorally congruent with targeted users.

Trial registration
NCT03671239 (14/09/2018).