Vaginal PrEP ring could offer three months of HIV protection
A new vaginal ring that slowly releases a pre-exposure prophylaxis (PrEP) drug could protect people with vaginas from HIV for up to three months according to new trial data.
The trial, conducted by U.S. National Institutes of Health-funded Microbicide Trials Network (MTN), assessed two different formulations of the ring that contains time-released dapivirine into the vagina, one contained 100mg dapivirine and the other 200mg – both last for 90 days.
The trial enrolled 49 healthy cis women without HIV, who were then divided into three groups
- 100mg dapivirine ring for 13 weeks
- 200mg dapivirine ring for 13 weeks
- A 30-day ring, replaced every four weeks
By the end of the study all three rings showed no safety concerns and were well-tolerated by study participants. When comparing dapivirine concentrations those using the 90 day rings had 1.3 – 1.9 times more dapivirine in bloody plasma, and 1.5 to 2.9 times more in vaginal fluids. There were also higher concentrations noted in cervical tissues.
This preliminary data suggests that 90-day ring may provide long-acting and durable HIV protection but has yet to be peer reviewed.
This new 90-day ring follows the approval, by the World Health Organisation (WHO), of the monthly dapivirine ring developed by the International Partnership for Microbicides (IPM). IPM is currently seeking approval for their monthly ring for use in Eastern and Southern Africa, as well as in the US via the Food and Drug Administration (FDA).
"Regulatory approval of the monthly ring would be an incredible milestone for women, who have been the face of the HIV epidemic in much of the world and need and deserve to have a range of safe and effective methods,"
"Hopefully, an extended-duration dapivirine ring that women replace every three months can be yet another option available to women in the not-too-distant future," study chair Dr. Albert Liu said in an MTN news release. He is clinical research director at the San Francisco Department of Public Health.