A Phase IIa clinical trial (REACH) has been initiated to assess the safety of oral pre-exposure prophylaxis (PrEP) and a vaginal ring in preventing HIV in southern Africa.
The trial is funded by the US National Institutes of Health (NIH) and is being conducted in 300 HIV-uninfected adolescent girls and young women aged 16 to 21 years at five sites in Kenya, South Africa, Uganda and Zimbabwe.
PrEP regimen comprises a daily oral tablet containing two anti-HIV drugs, tenofovir and emtricitabine.
The vaginal ring has to be replaced every month and is designed to continuously release anti-HIV drug dapivirine. It is currently under review by the European Medicines Agency (EMA).
Trial participants initially have to use each of these therapies for six months and then choose to use one or none of them for another six months.
The PrEP oral tablet is being supplied by Gilead Sciences, while the dapivirine ring is provided by the International Partnership for Microbicides (IPM).
Primary outcome measures of the trial are the frequency of Grade II or higher adverse events (AEs), detectable drug levels in blood, and residual drug levels in returned VRs.
It will also investigate secondary outcome measures such as the proportion of subjects reporting acceptability of the therapy and selecting the dapivirine ring over the oral tablets.
The trial is expected to be completed in June 2021.
Oral PrEP in combination with HIV prevention approaches is recommended by the World Health Organization (WHO) as a prevention choice for people at substantial HIV infection risk.
The investigational dapivirine ring was observed to be well-tolerated and minimised the risk of HIV by around 30% in African women aged 18 to 45 years in ASPIRE and The Ring Study trials.