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 and transgender women enrolled in a phase II, crossover trial comparing safety and acceptability of an oral tablet and a rectal gel used daily for HIV prevention. Participants reported adherence via daily text messages during 8-week periods. Trajectory analysis identified weekly patterns. Polytomous logistic regression identified characteristics associated with higher probability of trajectory group membership. 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 (OR = 4.76, 95% 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). 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:1.01–5.00), and to report a change in routine if gel was not used (OR = 5.26, 95% CI:1.23–100.00). Characteristics of participants likely to be high-adherers to product use vary according to product. Evaluation of acceptability prior to phase II/III trials could identify participants likely to maintain high adherence.

KEYWORDS:

• PrEP
• microbicides
• adherence
• SMS
• trajectory

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Rebecca Giguere http://orcid.org/0000-0002-6529-0550

Additional information

Funding

This work was supported by National Institute of Allergy and Infectious Diseases: [Grant Number UM1AI068615, UM1AI068633, UM1AI106707]; National Institute of Mental Health: [Grant Number P30 MH43520, P60 MD006902]; U.S. National Library of Medicine: [Grant Number R01 LM012355, T15 LM007079].