Genetic studies in mice have demonstrated that retinoic acid receptor alpha (RARα) deficiency leads to male infertility without affecting overall viability, suggesting that pharmacological inhibition of this receptor could be a viable contraceptive strategy. This review describes the use of experimental approaches to develop RARα-selective antagonists for male contraception. Initial studies with BMS-189453, a pan-RAR antagonist, showed significant testicular degeneration and reversible infertility in mice. The search for RARα-specific antagonists led to the development of YCT-529, a potent and selective RARα antagonist with favorable pharmacokinetics. YCT-529 demonstrated excellent in vivo efficacy in inhibiting spermatogenesis and inducing infertility in mice, with fertility recovery following drug discontinuation. YCT-529 is now in clinical development as a candidate for male contraception.
Keywords: Antagonist; Male contraception; Reversibility; Spermatogenesis inhibition; Vitamin A.
Copyright © 2025 The Authors. Published by Elsevier Inc. All rights reserved.