Contraline, a clinical-stage biopharmaceutical company focused on developing innovative male contraceptives, has secured $92.5 million in Series B financing to advance the late-stage development of its lead candidate, NES/T Gel, an investigational reversible hormonal contraceptive for men.
The financing round was co-led by BVF Partners L.P. and RA Capital Management, with participation from several prominent investors, including GV (Google Ventures), Lumira Ventures, Invus, and other new and existing backers. The funding marks a significant milestone for the company as it seeks to bring one of the first pharmaceutical contraceptive options for men closer to market.
Alongside the financing announcement, Contraline revealed that Iris van Alderwerelt van Rosenburgh, Ph.D., of BVF Partners, will join the company’s Board of Directors.
The proceeds from the investment will primarily support the continued development of NES/T Gel, a once-daily topical contraceptive that combines segesterone acetate, a synthetic progestin marketed as Nestorone, with testosterone. The treatment is designed to suppress sperm production while maintaining normal testosterone levels, potentially offering men a reversible and convenient contraceptive option without permanently affecting fertility.
The announcement comes after NES/T successfully completed a global Phase 2b clinical trial involving 462 couples. According to the company, the study produced encouraging results related to contraceptive efficacy, safety, tolerability, reversibility, and overall user acceptance. Contraline expects to begin Phase 3 clinical development in 2027, a critical step toward potential regulatory approval.
The company believes the need for additional contraceptive options remains significant. While women currently have access to a wide range of hormonal and non-hormonal birth control methods, choices for men have remained largely limited to condoms and vasectomy. Contraline’s leadership argues that expanding male contraceptive options could help distribute responsibility for family planning more evenly between partners.
Kevin Eisenfrats, co-founder and Chief Executive Officer of Contraline, described male contraception as one of the largest unmet needs in reproductive healthcare. He noted that survey data indicate more than 40 million men in the United States would consider using a novel male contraceptive, underscoring both the potential market opportunity and broader public health impact.
Investors participating in the financing emphasized the societal importance of developing new family-planning options. Representatives from BVF Partners and RA Capital Management highlighted the possibility that NES/T could become the first approved pharmacological contraceptive specifically designed for men, potentially transforming reproductive health and personal choice for millions of individuals and couples worldwide.
NES/T was originally developed by the Population Council in collaboration with the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), a division of the U.S. National Institutes of Health. Contraline holds exclusive worldwide rights to develop and commercialize the therapy.
In addition to NES/T, the company is advancing ADAM™, an investigational non-hormonal, long-acting, and reversible male contraceptive currently undergoing clinical development. Together, the programs position Contraline at the forefront of efforts to expand contraceptive innovation and redefine reproductive health options for men.