iconstar paper   HIV Articles  
Back grey arrow rt.gif
 
 
ASM: HIV-1 Seroconversion Across 17 International Demonstration Projects Using Pre-exposure Prophylaxis (PrEP) With Oral Emtricitabine/Tenofovir Disoproxil Fumarate (FTC/TDF)
 
 
  Reported by Jules Levin
ASM June 16-20 Boston, MA
 
Scott McCallister, David Magnuson, Rebecca Guzman, Valentina Shvachko, Keith Rawlings, Robertino Mera Gilead Sciences, Inc., Foster City, CA, USA

Clin1

Clin2

Program ABSTRACT
 
Background:
HIV-1 seroconversion rates in carefully managed PrEP clinical studies varied by the treatment population evaluated, from 1.2/100 person years (PY) in United Kingdom urban clinics (PROUD) to 1.9/100 PY in the US, South America and Africa (iPrEX). We collected HIV-1 seroconversion data with use of FTC/TDF for PrEP from diverse countries and populations in a real-world setting to compare to clinical study data.
 
Methods: Patient time exposure from 2011 through mid-2015 was collected from 4,981 HIV-negative adults participating in 17 ongoing international PrEP demonstration projects from North and South America, Asia, and Africa; all participants received open-label FTC/TDF for daily use. All studies conducted HIV-1 and sexually transmitted infection testing. Time exposed to FTC/TDF while at risk of seroconversion was analyzed; participants in deferred FTC/TDF and other non-PrEP arms were excluded and exact Poisson statistics were used to compute rates and confidence intervals.
 
Results: The 4,981 participants from the 17 studies had 4,171 PY of exposure to FTC/TDF. A total of 54 HIV-1 seroconversions occurred, a rate of 1.29/100 PY (95% CI: 0.97-1.69). Median time to seroconversion was 268 days, range 4-601 (IQR: 171-425). 9/54 (14.8%) reported signs or symptoms of acute retroviral syndrome at the time of seroconversion. Mean age of those who seroconverted: 25.1 + 7 years; 61% were <25 years old. 96% of those seroconverting were male, contributing 3826.2 PY of FTC/TDF exposure, for a rate of 1.36/100 PY (95% CI: 1.02-1.78). Women had 278.6 PYs of FTC/TDF exposure for a rate of 0.72/100 PY (95% CI: 0.09-2.60). 25/54 seroconverters were from the USA. Race for seroconverters: black 43%, mixed 39%, white 11%, Asian 2%. Genotypic resistance data for 18 of 54 seroconverters was available; 15/18 (83%) had wild-type virus, 3/18 had M184V/I; there were no reports of K65R or K70R.
 
Conclusions: This large meta-analysis of HIV-1 seroconversion data with the use of FTC/TDF for PrEP demonstrates a low overall seroconversion rate in a real world setting with an upper confidence interval below 2 infections per 100 PY. While these data are reassuring and inform prevention programs in diverse settings, more data are needed in women and transgendered individuals.

Clin3

Clin4

Clin5

Clin6

Clin7

Clin8

Clin9

 
 
 
 
  iconpaperstack View Older Articles   Back to Top   www.natap.org