Researchers at the Population Council, in collaboration with the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) are developing a Nestorone®/Testosterone gel, a novel reversible contraceptive for men that is designed to be absorbed through the skin with minimal side effects.
There is a growing interest and willingness among men in becoming more involved in family planning, and studies suggest that women would welcome male contraceptive choices. However, men have no contraceptive options other than vasectomy or condoms.
The need for effective and reversible methods of male contraception is widely recognized, but the development of effective options for men remains a challenge for the field. This is because the success of male hormonal contraception depends on near complete suppression of sperm production while maintaining healthy testosterone levels to maintain a man’s sexual drive (libido). A safe, effective, acceptable, reversible contraceptive for men requires an approach that will suppress sperm count in a well-defined period of time (e.g., ≤12 weeks) while maintaining testosterone levels in the normal range.
The Population Council has developed a contraceptive gel for men that can be applied once daily and absorbed through the skin of a man’s shoulders and upper arms. The gel contains the progestin Nestorone®, which has been shown to suppress sperm creation in men, and testosterone, which is already approved and marketed in gel form in the United States.
Previous clinical studies conducted with the Clinical Trial Network of the NICHD indicate that the use of the Nestorone®/Testosterone gel reduced sperm production to a level considered to indicate successful sperm suppression while maintaining healthy testosterone levels, and thereby minimizing side effects such as lower libido, acne, weight gain, and altered cholesterol levels.
Early research findings show that the Nestorone®/Testosterone gel is well tolerated with no serious adverse events. A Phase 2 study is currently underway to demonstrate the efficacy, safety, and acceptability of the gel when used by men in preventing pregnancy among couples in seven countries around the world. The trial, which began enrolling couples in 2018, is sponsored by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD).
Steady delivery of Nestorone®/Testosterone gel through the skin would be an easy-to-use, reversible contraceptive method controlled by men – other delivery methods tested have included injectables and implants. If approved by regulatory authorities, the Nestorone®/Testosterone gel would be the first-of-its-kind contraceptive for men.