Seroconversion while using dapivirine ring does not lead to drug-resistant HIV in African study

Not only is the dapivirine vaginal ring safe and effective in preventing seroconversions, it is also not associated with the development of drug-resistant HIV when the virus is acquired while using the ring, recently published research finds.

About This Study

“HIV Drug Resistance Assessment Among Women Who Seroconverted During the MTN-025/HOPE Open-Label Extension Dapivirine Vaginal Ring Trial“ was published online on Sept. 20, 2023, in Journal of Acquired Immune Deficiency Syndromes. The lead author is Urvi M. Parikh, Ph.D., of the University of Pittsburgh, Pennsylvania.

Key Research Findings

While the dapivirine vaginal ring is not being considered for pre-exposure prophylaxis (PrEP) in the U.S., it is approved for PrEP in sub-Saharan Africa. Studies there have found it to be safe and effective. Data from the latest of these studies, DELIVER, were published recently. As with other forms of biomedical HIV prevention, concerns remained that HIV seroconversions while on this PrEP could lead to drug-resistant virus.

In this open-label study, researchers sequenced the plasma samples of 38 women who seroconverted during an open-label study of the ring that was conducted among 1,456 HIV-negative women in sub-Saharan Africa. Most of the HIV acquisitions occurred in participants who had either not used the ring or done so inconsistently.

Three of the 38 women who tested positive had acute HIV at study enrollment, but none of their samples showed mutations indicating resistance to non-nucleoside transcriptase inhibitors (NNRTIs). Seven other samples had NNRTI resistance mutations. One of these showed reduced susceptibility to dapivirine but was from a woman who had not used the ring. Continuing to use this form of PrEP after seroconversion did not increase the risk of developing resistance.

Discussion Highlights and Implications for Practice

Between 10% and 30% of HIV circulating in the countries where the parent study was conducted is resistant to NNRTIs. Thus, the current study’s 20% rate of resistance mutations likely resulted from transmitted resistance, not dapivirine exposure, the researchers emphasized.

In addition, drug concentrations are higher in the vagina, with limited drug exposure in plasma, which may reduce the risk of drug resistance. Nonetheless, circulating NNRTI resistance should be monitored to assess its potential impact on the efficacy of the dapivirine ring, the authors said.

“Development of multipurpose rings that include levonorgestrel with dapivirine are underway to provide both HIV prevention and contraception from a single device,” the authors also noted.

By Barbara Jungwirth