Male contraceptive development: Update on novel hormonal and nonhormonal methods

BACKGROUND: Development of new methods of male contraception would address an unmet need for men to control their fertility and could increase contraceptive options for women. Pharmaceutical research and development for male contraception was active in the 1990s but has been virtually abandoned. The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) has supported a contraceptive development program since 1969 and supports the majority of hormonal male contraceptive development. Nonhormonal methods are also in development but are at earlier stages. CONTENT: Several hormonal male contraceptive agents have entered clinical trials. Single-agent products being evaluated include dimethandrolone undecanoate, 11-methyl-nortestosterone dodecyl carbonate, and 7-methyl-19-nortestosterone. A contraceptive efficacy trial of Nestorone ^® gel and testosterone gel in a single application will begin in 2018. Potential nonhormonal methods are at preclinical stages of development. Many nonhormonal male contraceptive targets that affect either sperm production or sperm function have been identified. Targeted pathways include the retinoic acid pathway, bromodomain and extraterminal proteins, and pathways for Sertoli cell– germ cell adhesion or sperm motility. Druggable targets include CatSper, the sperm Na/K-exchanger, TSSK, HIPK4, EPPIN, and ADAMs family proteins. Development of a procedure to reversibly block the vas deferens (initially developed in India in the 1980s) is undergoing early stage research in the US under the trade name Vasalgel™. SUMMARY: NICHD has supported the development of reversible male contraceptive agents. Other organizations such as the World Health Organization and the Population Council are pursuing male contraceptive development, but industry involvement remains dormant.