YCT529

YCT529 is a drug which acts as a potent and selective antagonist of the Vitamin A receptor retinoic acid receptor alpha (RAR-α). In studies on mice it produced a 99% reduction in sperm production, and it has proceeded to early stage human clinical trials as a potential male contraceptive.

The Vitamin A signalling system plays a number of important roles in bodily systems, such as the Immune system “It seems to me inherently unlikely that a compound with such activity would be free of side effects,” says Richard Sharpe, of the University of Edinburgh.