Nestorone (NES) is a synthetic progestogen designed with high specificity for the progesterone receptor. It is being investigated for use in hormonal contraceptives but is currently not used in any approved products internationally.
Wikipedia Entry Name
Soluble in DMSO, 5 mg/mL
3 tests showed no gene mutations and did not affect chromosomal integrity
Safety Profile Overview
Similar safety profile to progestogens found in approved oral contraceptives; no significant or unusual toxicities.
Progesterone Receptor Activity
Androgen Receptor Activity
Estrogen Receptor Activity
Glucocorticoid Receptor Activity
Binds to GR but does not show activity in in vivo assays
Mineralocorticoid Receptor Activity
Elimination Half-Life (t1/2)
Serum Protein Binding
Binds to albumin. Does not bind to SHBG.
Inhibits 3β-hydroxysteroid dehydrogenase type 2 (HSD3B2) and reduces the biosynthesis of several endogenous steroids.
Route of Administration
Parenteral. Orally inactive.
Minor metabolite. Also a degradant (see Nestorone Impurity 13). HPLC and MS.
Major metabolite as identified by Prasad et al. (19 total metabolites found but only 2 identified). HPLC and MS.
Most abundant metabolite in mouse plasma at 1 h post administration.
120 times less potent PR activity than Nestorone in human PR (hPR) transactivation assay (EC50 = 24 pM for NES vs. 2850 pM for metabolite). GC/MS-MS.
Identified in vitro, detected in plasma and brain of mice. Most abundant metabolite in mouse brain at 30 min post administration. 17 times less potent PR activity than nestorone in human PR transactivation assay (EC50 = 410 pM vs. EC50 of Nestorone = 24 pM).