Hexavalent sperm-binding IgG antibody released from vaginal film for development of potent on-demand nonhormonal female contraception
Bhawana Shrestha, Kathleen L. Vincent, Alison Schaefer, Yong Zhu, Gracie Vargas, Massoud Motamedi, Kelsi Swope, Josh Morton, Carrie A. Simpson, Henry Pham, Miles B. Brennan, Michael Pauly, Larry Zeitlin, Barry Bratcher, Kevin J. Whaley, Thomas R. Moench, Samuel K. Lai
Abstract
Significance Nearly half of all pregnancies in the United States are unintended due to millions of women avoiding available hormonal contraceptive methods as a result of real and/or perceived side effects associated with the use of exogenous hormones. Topical vaginal delivery of antisperm monoclonal antibodies that could agglutinate sperm into clusters too large to penetrate mucus and prevent sperm from reaching the egg represents a potentially safe and potent mechanism for nonhormonal contraception. We report here the engineering of a vaginal film loaded with hexavalent (i.e., 6 Fab) antisperm IgG, made using GMP manufacturing processes, that possesses significantly superior agglutination potency than the parent IgG, enabling potent on-demand nonhormonal contraception via effectively agglutinating all human sperm within minutes.