Evaluation of Efficacy, Safety, and Reversibility of Combination Regimen of Cyproterone Acetate and Testosterone Buciclate in Bonnet Monkeys

In a study from 2000, researchers tested a contraceptive regimen combining cyproterone acetate (CPA) and testosterone buciclate (TB) on bonnet monkeys. Group II, with 6 monkeys, received 5 mg CPA daily and 40 mg TB at specific intervals, achieving azoospermia by day 120, which lasted until day 210, with sperm levels returning to baseline by day 330. Group III, also with 6 monkeys, received the same CPA dose but a higher TB dose (80 mg) and did not achieve consistent azoospermia, nor did sperm concentration return to baseline by the study's end. Elevated serum testosterone levels in both groups normalized by day 330, and no significant changes in lipid profiles or liver function were observed, indicating safety. The study concluded that the right dosage of CPA and TB can be an effective, safe, and reversible male contraceptive method.