Trajectory of use over time of an oral tablet and a rectal gel for HIV prevention among transgender women and men who have sex with men

Abstract

We examined product adherence among 187 men who have sex with men (MSM), and transgender women (TW), enrolled in MTN-017, a phase II, crossover trial comparing safety and acceptability of oral emtricitabine/tenofovir disoproxil fumarate tablet (daily oral) and tenofovir 1% reducedglycerin gel used rectally (daily gel) or before and after receptive anal intercourse (RAI) (rectal gel) for HIV prevention in the US, Thailand, Peru and South Africa. Participants reported adherence via daily text messages during 8-week periods of product use. Trajectory analysis identified weekly adherence patterns. Polytomous logistic regression identified characteristics associated with higher probability of being in a particular trajectory group. We identified 3 groups per product: high-adherers (72% daily oral, 70% daily gel); decreasing-adherers (20% daily oral, 22% daily gel); and low-adherers (8% daily oral, 9% daily gel). Daily oral high-adherers (compared with low-adherers) were more likely to self-identify as male [odds ratio (OR)=4.76, 95% confidence interval (CI):1.35-16.67], to have more sexual partners (OR=1.67, 95% CI:1.04-2.63), and to find the tablet easy to swallow (OR=2.22, 95% CI:1.08-4.76), and less likely to report not liking the tablet as a reason for not using it (OR=0.43, 95% CI:0.19-0.96). Daily gel high-adherers (compared with low-adherers) were more likely to be older (OR=1.16, 95% CI: 1.05-1.28), to find gel application easier at the last few applications (OR=2.27, 95% CI:1.

A latent trajectory analysis of young sexual and gender minorities’ adherence to three rectal microbicide placebo formulations (MTN-035; a randomized crossover trial)

“…Using latent class trajectory analyses, we were able to understand differences in participants’ RM use trajectories using their SMS self-reports. Similar to prior research on rectal gel use for HIV prevention among transgender women and MSM [ 17 ], we found our sample could be characterized based on their product use over time. We observed two group-based trajectories across the three modalities, with the two trajectories being distinguished by the quantity of product usage reported per week.…”

“…We examined whether participants’ use of each placebo modality (douche, insert, and suppository) changed over time. Given prior research noting the presence of diverse trajectories [ 16 , 17 ], we hypothesized that we would observe at least two trajectories for each product: one noting an increase in product use over time, and another indicating consistent product use over time. We then examined whether RM product use was associated with participants’ baseline sociodemographic characteristics and sexual behaviors.…”

Adherence to daily HIV pre-exposure prophylaxis in a large-scale implementation study in New South Wales, Australia

“…To characterize trajectory groups identified using GBTM, univariable, and multi-variable ordinal logistic regression models were developed. Predictors considered in the analyses included: age at first dispensing (<25, [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44], and !45 years); sexual identity (gay/ homosexual, bisexual, and heterosexual/other); country of birth (Australia; other high-income English speaking countries, including Canada, Ireland, New Zealand, United Kingdom, and United States; Asian countries; and other); published estimates of the proportion of males identifying as gay in the postcode of residence (!20%, 10-20%, 5-9%, and <5%) [17]; a recent diagnosis (last 3 months) of rectal gonorrhoea, rectal chlamydia, or infectious syphilis as assessed at study baseline; and recent use of crystal methamphetamine. Variables with a P value of <0.10 in univariable analysis were included in multivariable analysis to allow adjustment for confounding.…”

“…Based on quarterly MPR, patterns of PrEP adherence trajectory identified using GBTM were strongly associated with HIV incidence. Internationally, two much smaller cohort studies with shorter follow-up used the GBTM method to summarise PrEP adherence which had been determined by daily text messages to participants [25,26]. One of the studies followed 181 men in California for a total of 48 weeks and reported that the four adherence trajectories identified were highly associated with TDF/FTC concentration in blood samples [27].…”

Preference for using a variety of future HIV pre‐exposure prophylaxis products among men who have sex with men in three US cities

“…Long-acting injectable (LAI) forms of PrEP have also been shown to be popular as a potential administrative method [3,6,7], and LAI was recently found to be efficacious in preventing HIV infection [8]. The sparse but emerging literature on product preferences speaks to the need to prepare for a host of potential products and varying preferences among MSM, and a particular need for quantitative research in a large and diverse sample of MSM [6,9,10]. In this study, we assess self-reported likelihood of using various HIV prevention products, including a LAI form of PrEP and sexual event-based pills, gels and anal suppositories among a large and diverse sample of MSM in three US cities.…”