Megestrol acetate

Megestrol acetate

Clinical data
Pregnancy category	US: X (Contraindicated)
Routes of administration	Oral (tablets, suspension)
ATC code	G03AC05 (WHO)
Legal status
Legal status	In general: ℞ (Prescription only)
Pharmacokinetic data
Bioavailability	poor
Protein binding	Majority to albumin (no affinity for SHBG or CBG)
Biological half-life	13–105 hours (mean 34)
Identifiers
IUPAC name 17-(Acetyloxy)-6-methylpregna-4,6-diene-3,20-dione
Synonyms	BDH-1298, NSC-71423
CAS Number	595-33-5
PubChem CID	11683
DrugBank	DB00351
ChemSpider	11192
ECHA InfoCard	100.008.969
Chemical and physical data
Formula	C24H32O4
Molar mass	384.509 g/mol
3D model (Jmol)	Interactive image
SMILES O=C4\C=C3\C(=C/[C@@H]1[C@H](CC[C@@]2([C@@](OC(=O)C)(C(=O)C)CC[C@@H]12)C)[C@@]3(C)CC4)C
InChI InChI=1S/C24H32O4/c1-14-12-18-19(22(4)9-6-17(27)13-21(14)22)7-10-23(5)20(18)8-11-24(23,15(2)25)28-16(3)26/h12-13,18-20H,6-11H2,1-5H3/t18-,19+,20+,22-,23+,24+/m1/s1 Key:RQZAXGRLVPAYTJ-GQFGMJRRSA-N

Megestrol acetate (MGA) (INN, USAN, BAN, JAN) (brand names Megace, Megace ES), also known as 17α-acetoxy-6-dehydro-6-methylprogesterone, is a steroidal progestin of the 17α-hydroxyprogesterone group that is used in the treatment of breast and endometrial cancer and as an appetite stimulant. It is the 17α-acetate ester of megestrol, which, in contrast to MGA, was never marketed for clinical use. The term megestrol is often inappropriately used as a synonym for MGA, and when it is used, it almost always refers to MGA rather actually than megestrol.

MGA is used mainly as an appetite stimulant in a variety of conditions and as an antineoplastic agent in the treatment of breast, endometrial, and prostate cancers. When given in relatively high doses, it can substantially increase appetite in most individuals, even those with advanced cancer, and is often used to boost appetite and induce weight gain in patients with cancer or HIV/AIDS-associated cachexia. It is also used as a contraceptive in combination with an estrogen at relatively low doses.