|Other names||TZP-4238; Gestoxarone acetate; 2-Oxachloromadinone acetate; 17α-Acetoxy-6-chloro-2-oxa-6-dehydroprogesterone; 17α-Acetoxy-6-chloro-2-oxapregna-4,6-diene-3,20-dione|
|By mouth (tablets)|
|Drug class||Steroidal antiandrogen; Progestogen; Progestin; Progestogen ester|
|Protein binding||Osaterone acetate: 90%|
15β-Hydroxyosaterone acetate: 80%
(Both mainly to albumin)
|Elimination half-life||Dogs: 80 hours to 197 ± 109 hours|
|Chemical and physical data|
|Molar mass||406.900 g/mol g·mol−1|
|3D model (JSmol)|
Osaterone acetate is an antiandrogen, and hence is an antagonist of the androgen receptor, the biological target of androgens like testosterone and dihydrotestosterone. It is also a progestin, or a synthetic progestogen, and hence is an agonist of the progesterone receptor, the biological target of progestogens like progesterone.
Osaterone acetate is used in veterinary medicine in Europe in the treatment of benign prostatic hyperplasia (BPH) in dogs. It has been found to produce remission of clinical symptoms of BPH in 83% of dogs for six months after a single one-week course of treatment, and can be used long-term.
Side effects of osaterone acetate include diminished sperm quality (for up to 6 weeks post-treatment), transient elevation of liver enzymes (caution should be observed with known liver disease), vomiting, diarrhea, polyuria/polydipsia, lethargy, and hyperplasia of the mammary glands. It can also decrease cortisol levels, interfere with adrenocorticotropic hormone response, induce or exacerbate adrenal insufficiency, and exacerbate diabetes mellitus.
Osaterone acetate is a steroidal antiandrogen, progestin, and antigonadotropin. It has virtually no estrogenic or androgenic activity. Its side-effect profile indicates that it possesses clinically relevant glucocorticoid activity. An active metabolite of osaterone acetate, 15β-hydroxyosaterone acetate, has potent antiandrogenic activity similarly to osaterone acetate. Osaterone acetate treats BPH in dogs by reducing the actions of androgens in the prostate gland.
Osaterone acetate, also known as 2-oxachloromadinone acetate, as well as 17α-acetoxy-6-chloro-2-oxa-6-dehydroprogesterone or 17α-acetoxy-6-chloro-2-oxapregna-4,6-diene-3,20-dione, is a synthetic pregnane steroid and a derivative of progesterone and 17α-hydroxyprogesterone. It is a derivative of the less potent chlormadinone acetate. The medication is the C17α acetate ester of osaterone.
Osaterone acetate is marketed under the brand name Ypozane by Virbac.