Phase II clinical trial of a vas deferens injectable contraceptive for the male
Guha, S.K.; Singh, G.; Ansari, S.; Kumar, S.; Srivastava, A.; Koul, V.; Das, H.C.; Malhotra, R.L.; Das, S.K.
Contraception 56(4): 245-250
1997
ISSN/ISBN: 0010-7824 PMID: 9408706 DOI: 10.1016/s0010-7824(97)00142-xDocument Number: 270756
A Phase I clinical trial documented the safety of an intra-vas deferens injection of a contraceptive agent (Risug) containing up to 140 mg of styrene maleic anhydride (SMA) in a solvent vehicle of dimethylsulfoxide. This Phase II study sought to determine whether a single injection of a fixed dose of SMA into the lumen of the vas deferens controls fertility for a period of at least 12 months. 12 male subjects whose wives were not using a contraceptive method were administered 60 mg of SMA bilaterally. This regimen produced sustained azoospermia in all 12 subjects, with no changes in other parameters over the course of the 12-month study period. Spermatozoa all along the length of the vas deferens appeared to be inactivated immediately following injection. No pregnancies were reported. The findings confirm the safety of this method and indicate that the treatment leads to azoospermia for at least 1 year.