s of promegestone include menstrual irregularities among others. It has no androgenic side effects.
Pharmacology
Pharmacodynamics
Promegestone is a progestogen, or an agonist of the progesterone receptor. It has about 200% of the affinity of progesterone for the PR. The endometrial transformation dosage of promegestone is 10 mg per cycle and its ovulation-inhibiting dosage is 0.5 mg/day. Promegestone has weak glucocorticoid activity in addition to its progestogenic activity. Conversely, it has no androgenic, estrogenic, mineralocorticoid, or other hormonal activity. It appears to possess antiandrogenic activity. Its major metabolite trimegestone has weak antimineralocorticoid and antiandrogenic activity. In addition, promegestone has been found to possess some neurosteroid activity by acting as a non-competitive antagonist of the nicotinic acetylcholine receptor, similarly to progesterone.
Pharmacokinetics
Following oral administration, peak serum levels of promegestone are reached after 1 to 2 hours. The medication is mainly bound to albumin; it does not bind to sex hormone-binding globulin, and binds only weakly to corticosteroid-binding globulin. The metabolism of promegestone is mainly via hydroxylation at the C21 position and at other positions. Progesterone is similarly hydroxylated at the C21 position, into 11-deoxycorticosterone. However, the C9 double bond of promegestone greatly limits the A-ring reduction that progesterone undergoes, resulting in 21-hydroxylation being the main route of metabolism for promegestone. The medication is stereoselectively metabolized into trimegestone, the 21-hydroxy metabolite, which is the main compound found in plasma; it circulates at levels approximately twice those of promegestone itself. In addition, trimegestone has more than three-fold higher affinity for the PR than does promegestone. As such, promegestone is largely a prodrug of trimegestone. A second metabolite, 21-hydroxypromegestone, circulates at far lower concentrations - and. The elimination half-life of trimegestone is 13.8 to 15.6 hours. Promegestone, trimegestone, and 21-hydroxypromegestone are not excreted in urine, while 3% of a dose is recovered as the glucuronide and/or sulfate conjugate of trimegestone and 1% of a dose is recovered as the glucuronide and/or sulfateconjugate of 21-hydroxypromegestone.
Promegestone was first described in the literature in 1973 and was introduced for medical use in France in 1983. It was developed by Roussel Uclaf in France.
Society and culture
Generic names
Promegestone is the generic name of the drug and its, while promégestone is its. It is also known by its developmental code nameR-5020 or RU-5020.