PrEP Adherence Patterns Strongly Affect Individual HIV Risk and Observed Efficacy in Randomized Clinical Trials.

ABSTRACT:

Background

Randomized controlled trials (RCTs) suggest that the efficacy of tenofovir-based preexposure prophylaxis (PrEP) strongly depends on the consistency of PrEP use. We explore how the patterns of pill taking and waning of PrEP protection may affect PrEP efficacy for HIV prevention.

Methods

A 2-arm RCT was simulated by mathematical models assuming that the prescribed daily doses were skipped periodically, randomly, or in large blocks. Risk-driven adherence, in which PrEP was taken when sex was expected, was also investigated. Three temporal PrEP protection profiles were explored: long (5 days), intermediate (3 days), and short (24 hours). Modeling results were compared to the efficacy observed in completed RCTs.

Results

The expected PrEP efficacy was 60% with pe

SUBMITTER: Dimitrov DT 

PROVIDER: S-EPMC4925182 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature