Oral and vaginal HIV pre-exposure prophylaxis product attribute preferences among female sex workers in the Mexico-US border region

Abstract

To assess the potential uptake of HIV pre-exposure prophylaxis (PrEP) products among female sex workers (FSWs) vulnerable to HIV infection, we examined the influence of product attributes on willingness to use products among 271 HIV-negative FSWs in Tijuana and Ciudad Juarez, Mexico (2016-2017). Via five-point Likert scale ratings, participants indicated their willingness to use hypothetical products with six attributes: formulation (pill, gel, liquid, or ring), frequency of use (daily, on-demand, or monthly), cost per use (10 or 200 pesos), effectiveness (40% or 80%), side effects (none or mild), and access point (healthcare clinic or non-governmental organization). Conjoint analysis was used to determine the impact of attributes on product ratings and identify preferred product attributes. Multinomial logistic regression was used to identify factors associated with formulation preferences. In both cities, formulation and frequency of use had the greatest impact on ratings. Participants in Ciudad Juarez indicated a strong preference for oral pills, whereas participants in Tijuana indicated roughly equal preferences for oral pills and vaginal gels. Monthly product use was preferred in both cities. Compared to preferring oral pills (38%), preferring vaginal gels (28%) was associated with practicing vaginal lubrication (adjusted odds ratio = 2.08; 95% confidence interval: 1.07-4.04). Oral PrEP may be acceptable to many FSWs in Tijuana and Ciudad Juarez; however, continued development of behaviorally-congruent vaginal PrEP products may also facilitate uptake and ensure sufficient coverage.

Eliciting Preferences for HIV Prevention Technologies: A Systematic Review

“…Of the 21 CA studies, analysis methods included individual-specific, mean, and/or relative impact scores (7, 33%) [ 54 – 60 ]; mean ratings (5, 24%) [ 61 – 65 ], relative importance scores or interest values (4, 19%) [ 64 – 67 ]; modified Borda count method (1) [ 68 ]; part-worth utilities (4, 19%) [ 64 – 66 , 69 ]; hierarchical Bayes estimation (2, 10%) [ 70 , 71 ], and linear regression (1) [ 72 ]. To measure preference heterogeneity, two CA studies used subgroup analyses or stratification [ 69 , 70 ]; and one used latent class analysis [ 66 ].…”

“…Nineteen studies examined PrEP [ 33 , 34 , 36 , 40 , 43 , 46 , 49 , 51 , 61 , 64 – 66 , 70 , 71 , 78 , 79 , 83 , 90 , 91 , 101 ].…”

“…The most common PrEP product design attributes were frequency of dosing (daily, monthly) and product formulation, which necessarily overlap (pills: daily; injections: monthly). Some studies found that dosing frequency was unimportant compared to other attributes [ 43 , 61 , 79 ], while other studies showed preferences for daily pills [ 33 , 40 , 65 , 71 ], for monthly or bimonthly injections or implants [ 51 , 70 , 91 ], or for on-demand dosing (with sexual encounters) of rectal gels [ 64 , 79 ]. Formulation (pills, injections, rings, gel) was found to be variously as important as efficacy [ 29 ], even more important than efficacy [ 64 ], or secondary to efficacy [ 91 ].…”

A Review of Pre-Exposure Prophylaxis Adherence among Female Sex Workers

“…In the meantime, there is a need to consider existing vaginal practices to ensure the development of safe and effective vaginal PrEP products. 58,59 Implementation of various PrEP product formulations, including behaviorally-congruent vaginal gels and douches, have been shown to enhance future PrEP uptake and adherence and to ultimately reduce the burden of HIV among FSWs. 59 However, reports have warned of a potential interaction or dilution of PrEP effectiveness with concomitant use of vaginal washing or lubrication with vaginal gel-or douche-based PrEP products.…”

“…58,59 Implementation of various PrEP product formulations, including behaviorally-congruent vaginal gels and douches, have been shown to enhance future PrEP uptake and adherence and to ultimately reduce the burden of HIV among FSWs. 59 However, reports have warned of a potential interaction or dilution of PrEP effectiveness with concomitant use of vaginal washing or lubrication with vaginal gel-or douche-based PrEP products. 60 Some options that have been proposed to avert the daily usage of PrEP is an intermittent protocol.…”