Male Contraception

This is a Phase 1b/2a open-label, dose escalation 3 part-study, 28-day, 90-day or 180 day repeat dose study of YCT-529 in healthy males who have decided to have a vasectomy and are waiting for the procedure and for men who have decided not to father children in the future. The study is aimed at evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics and to assess sexual function and mood.

NLS-133-CLIN001 is a Phase 2a study designed to assess the safety, tolerability, and effects of NLS-133 (combination of two FDA-approved agents) compared to an active control (FDA-approved pharmacologic agent) or placebo on semen volume and sperm count in 10 in healthy men. Participants will be randomized in a crossover design to receive a single dose of NLS-133, an active control or placebo either 90 or 180 minutes prior to collection of semen. Sperm parameters measured will be count, motility and morphology. A brief questionnaire will be completed by each subject during each treatment cycle that addresses orgasm and ejaculation quality. Safety monitoring will include adverse event reporting, laboratory assessments, and vital signs.