Daré Bioscience announced positive interim safety and efficacy results from its ongoing Phase 3 clinical trial evaluating Ovaprene®, the company's investigational monthly, hormone-free intravaginal contraceptive. The trial's independent Data Safety Monitoring Board (DSMB) conducted a planned interim analysis focused on reviewing safety data and recommended the study continue without modification.
Interim Efficacy and Safety Results
At the time of the interim analysis, approximately 9% of the women treated in the study had experienced a pregnancy, a rate consistent with the company's expectations based on the results of the pre-pivotal postcoital test clinical study of Ovaprene. These interim findings support Ovaprene's potential as a meaningful hormone-free alternative.
No new safety or tolerability concerns were identified. Approximately 17% of participants discontinued the study due to vaginal odor, the most commonly reported product-related adverse event. No serious safety concerns were identified, and overall tolerability was favorable. Participants who had completed the study reported they would be very likely or likely to use Ovaprene if it became available.
"We are encouraged by these interim results, which reinforce the potential of our hormone-free contraceptive candidate to provide women with a meaningful alternative to existing hormonal and non-hormonal methods," said Sabrina Martucci Johnson, President and CEO of Daré Bioscience. "With millions of women in the U.S. seeking effective, hormone-free birth control, Ovaprene has the potential to address a significant unmet need and transform the contraceptive landscape."
Contraceptive Landscape Context
According to the FDA's birth control guide, the number of pregnancies expected using short-acting hormonal contraceptive methods (oral contraceptives, the patch, and the vaginal ring) is seven per 100 women, and the number of pregnancies expected using male condoms and diaphragms or sponges with spermicide is 13 and 17 per 100 women, respectively. There currently are no FDA-approved, hormone-free, monthly intravaginal contraceptives.
Trial Design and Objectives
The ongoing pivotal Phase 3 trial is a multicenter, single-arm, open-label study enrolling women aged 18–40 across 5 sites. As of the interim analysis, approximately 115 participants were ongoing or had completed the study. The target enrollment is approximately 250 participants completing approximately 12 months of use.
The primary objective of the study is to assess the typical use pregnancy rate over 13 menstrual cycles, or the estimated Pearl Index for Ovaprene. Secondary objectives are to assess Ovaprene's 13-cycle use cumulative pregnancy rate, safety, acceptability, product fit/ease of use, and assessments of vaginal health.
Commercial Partnership with Bayer
Bayer received the right to obtain exclusive U.S. rights to commercialize the product, following completion of the pivotal clinical trial if Bayer, in its sole discretion, makes a $20 million payment to Daré. Daré may receive up to $310 million in commercial milestone payments, plus double-digit tiered royalties on net sales. The potential $20 million payment and royalty payments are subject to a third party's minority interest under a royalty purchase agreement entered into in April 2024.
Johnson noted that the company looks forward to the completion of the study and the final analysis of study endpoints, including the primary endpoint of pregnancy rate calculated using the Pearl Index.
