Gossypol.

Abstract

The male contraceptive gossypol was developed by Chinese workers and tested on 10,000 male volunteers over a period of 5-8 years. It was effective in 99.8% of the cases. It acts also as an antiviral and antifungal agent inhibiting Trypnosone and Plasmodium, which cause Chagas and malaria respectively. This study also supports the efficacy of gossypol. Cellular and molecular lesions in the testis occurred with gossypol. Animal models have shown spermatogenesis after drug withdrawal. Bonnet monkey results support significantly reduced fertility. In vivo and in vitro work has been conducted in order to isolate the differential effects of optical isomers. The current results of unwanted side effects are 1) failure of recovery of spermatogenesis, and 2) hypokalemia. An operational model of action of gossypol on the testis is under development.