Preferences for HIV pre-exposure prophylaxis formulations and delivery among young African women: results of a discrete choice experiment

Abstract

Oral HIV pre-exposure prophylaxis (PrEP) is highly effective, but adherence is challenging for young women. Products centred around women?s preferences could address adherence barriers. Using a longitudinal discrete choice experiment (DCE), we examined young African women?s preferences around PrEP product formulation and delivery attributes before and after initiating oral PrEP. We enrolled HIV-negative women from six African countries in a prospective cohort from August 2022 to June 2023. Women completed two DCEs on PrEP products and PrEP delivery. At enrolment and month 1, participants completed the DCE about PrEP products with 16 randomly assorted choice sets assessing product form and dosing, dose forgiveness, drug reversibility, weight change and antiretroviral or immune-based mechanism attributes. At month 3, participants completed the DCE about PrEP delivery evaluating preferences related to location to collect doses, packaging, product storage, type of HIV test and costs. Preference weights (PW) were estimated with a hierarchical Bayesian model; higher positive numbers indicate greater preference for an attribute. Importance scores compare relative importance across the five attributes; higher scores indicate greater importance. Two thousand eight hundred and forty-seven women completed enrolment and month 1 DCEs; the median age was 24 years (range: 16–30) and 92.8% initiated daily oral PrEP. Product form and dosing was the most important attribute at enrolment and month 1. At enrolment, women preferred small oral pills taken monthly (preference weight [PW]: 0.67; 95% confidence interval [CI]: 0.58−0.77), and at month 1, they preferred a 6-monthly injection (PW: 0.56; 95% CI: 0.46−0.65). In the month 3 DCE, location was the most important PrEP delivery attribute with a strong preference for a youth-friendly or non-governmental organization (PW: 0.25; 95% CI: 0.19−0.30) or health facility (PW: 0.21; 95% CI: 0.17−0.25); mobile clinic or van was least preferred. The cost of the product was the second most important product delivery attribute. Young African women preferred discreet, less frequently administered PrEP formulations, particularly after 1 month of taking daily oral PrEP. Long-acting formulations are needed to meet women?s preferences. Coupled with the preferred PrEP delivery location and cost, the highlighted PrEP product characteristics have the potential to increase PrEP uptake.