ADAM, a long-term, injectable male birth control, shows promise at AUA 2025

Nathan Lawrentschuk, MBBS, PhD
Credit: Epworth Healthcare

A reliable, hydrogel-based male contraceptive could soon be a reality, according to new data from the American Urological Association's (AUA) 2025 Annual Meeting.

At the meeting, investigators presented data from a 90-day safety analysis of 25 men from the first-in-human trial of ADAM, a proprietary water-soluble hydrogel injected into the vas deferens to block sperm transport.¹

“We're excited by its early success, but we know there's much more work to do, but a viable male contraception is essential, I believe, in today's environment,” explained principal investigator Nathan Lawrentschuk, MBBS, PhD, urologist and urologic oncologist as well as a professor at the University of Melbourne. “And ADAM, I'm certain is going to be part of the future moving forward.”

Administered in an outpatient setting requiring locatl anesthesia, ADAM is injected into the vas deferens and is designed to block sperm traveling through without impacting sensation or ejaculation. According to developer Contraline, who also sponsored the first-in-human trial, these sperm that are blocked begin to naturally degrade and become absorbed. Following the conclusion of its lifespan, the hydrogel liquifies, which removes the barrier to sperm flow.

According to data presented by Lawrentschuk at AUA 2025, the 90-day safety profile of ADAM, a hydrogel-based male contraceptive, was assessed in an ongoing, open-label, single-arm, multi-center, dose-ranging trial involving 25 healthy men with normal semen parameters based on WHO 5th edition criteria.¹

To administer ADAM, investigators used a no-scalpel vasectomy (NSV) approach, which requires the vas deferens to be externalized and cannulated with a 24G over-the-needle catheter, enabling injection of ADAM into the lumen with a proprietary automated injector under local or general anesthesia. Participants were divided into 4 dosing cohorts and monitored for treatment-emergent and unrelated adverse events. According to the abstract, all 50 implantations were successful, confirmed by vas deferens cannulation, with no procedural adverse events reported.¹

During the 90-day follow-up, 76 adverse events were recorded, with 84.2% classified as mild, 14.5% as moderate, and 1.3% as severe, all anticipated. A single participant experienced a serious adverse event—colitis secondary to a dental infection, which investigators deemed unrelated to ADAM or the procedure. Most adverse events (71%) occurred within the first 14 days post-procedure and were consistent with standard NSV recovery. Investigators pointed out there were no differences in adverse event severity or relationship to ADAM across dosing cohorts.¹

“These exciting studies presented at AUA 2025 reflect new possibilities in male fertility and contraception research,” said Raevti Bole, MD, a men’s health urology specialist at the Cleveland Clinic.² “For the first time, we’re seeing promising safety results from a reversible, non-hormonal male birth control that may fit the needs of couples who need a secure contraceptive option but are not ready for something permanent.”

Less than a week before the presentation of 90-day safety data at AUA 2025, Contraline announced positive 24-month findings from the ADAM trial. According to the press release from Contraline, 2 participants have become the first to reach azoospermia at 24 months.³

The release points out additional participants remain in the trial, with ongoing efficacy observed at 12, 15, 18, and 21 months, measured by lab-based semen analysis and at-home sperm testing. The release also highlighted all observed adverse events were consistent with the expected treatment profile and there were no unexpected safety concerns.³

“Our goal was to create a male contraceptive option lasting two years, responding directly to consumer needs,” said Alexander Pastuszak, MD, PhD, chief medical officer at Contraline, in the press release.³ “These findings confirm that ADAM, our novel water-soluble hydrogel, can achieve the intended lifespan. We remain optimistic about its safety, efficacy, and reversibility, and its potential to give men and couples greater reproductive control.”

References:

1. Lawrentschuk N, Chin P, Chung E. PD06-02 INITIAL 90-DAY SAFETY FINDINGS FROM A FIRST-IN-HUMAN STUDY OF ADAM: AN INNOVATIVE HYDROGEL DESIGNED FOR MALE CONTRACEPTION. J Urol. 2025;213(5S):e169. doi:10.1097/01.JU.0001109764.27496.08.02

2. American Urological Association. Studies Show Breakthroughs in Male Contraception, Including First Male Contraceptive Hydrogel - American Urological Association. AUAnet.org. Published April 26, 2025. Accessed April 26, 2025. https://www.auanet.org/about-us/media-center/press-center/studies-show-breakthroughs-in-male-contraception-including-first-male-contraceptive-hydrogel/.

3. Contraline. Announcing 24-Months of Safety and Efficacy Results from the First-in-Human Trial of ADAM^TM. Contraline.com. Published April 24, 2025. Accessed April 26, 2025. https://www.contraline.com/news/c5iloq6ImM5ypU01JDbxoso/.