Profile of the Progesterone Derivative Chlormadinone Acetate: Pharmacodynamic Properties and Therapeutic Applications

Chlormadinone acetate (CMA), a progesterone derivative synthesized in 1961, is used in hormone replacement therapy and contraception. It has a stronger progestogenic effect than progesterone and is anti-estrogenic, with no androgenic effect at contraceptive and HRT doses. CMA also exhibits a slight glucocorticoid effect, a pronounced anti-androgenic effect, and no anti-mineralocorticoid effect. Its anti-androgenic action is due to its competitive binding to androgen receptors and inhibition of 5alpha-reductase, with the dosage being critical to avoid agonistic effects. CMA has been used for over 20 years in contraception for patients at arterial risk due to its strong anti-gonadotropic effect. Clinical studies, lasting up to 2.5 years, have shown CMA to be metabolically tolerable. Its combination with ethinyl estradiol in contraceptives like Neo Eunomin and Belara has been highly successful, offering excellent contraceptive efficacy, tolerability, adherence, and benefits for dysmenorrhea, skin, and hair conditions.