Δ4-Tibolone Explained

δ⁴-Tibolone (developmental code name ORG-OM-38), also known as 7α-methylnorethisterone or as 7α-methyl-17α-ethynyl-19-nortestosterone, is a synthetic androgen and progestin which was never marketed.^{[1] [2]} The compound is a major active metabolite of tibolone, which itself is a prodrug of δ⁴-tibolone along with 3α-hydroxytibolone and 3β-hydroxytibolone (which, in contrast to δ⁴-tibolone, are estrogens). Tibolone and δ⁴-tibolone are thought to be responsible for the androgenic and progestogenic activity of tibolone, while 3α-hydroxytibolone and 3β-hydroxytibolone are thought to be responsible for its estrogenic activity.

See also

• List of androgens/anabolic steroids
• List of progestogens

Notes and References

1. Kuhl H . Pharmacology of estrogens and progestogens: influence of different routes of administration . Climacteric . 8 . 3–63 . 2005 . Suppl 1 . 16112947 . 10.1080/13697130500148875 . 24616324 .
2. Escande A, Servant N, Rabenoelina F, Auzou G, Kloosterboer H, Cavaillès V, Balaguer P, Maudelonde T . Regulation of activities of steroid hormone receptors by tibolone and its primary metabolites . J. Steroid Biochem. Mol. Biol. . 116 . 1–2 . 8–14 . 2009 . 19464167 . 10.1016/j.jsbmb.2009.03.008 . 18346113 .