Nestorone Acetate CAS:7759-35-5

Nestorone is a potent progesterone receptor agonist with no androgenic, estrogenic, or glucocorticoid-like activities. Nestorone has been used as a female contraceptive, and recent studies inidicate that it may be useful as a male contraceptive as well. It has also been shown to have neurogenic and neuroprotective activity.

Segesterone acetate (SGA), sold under the brand names Nestorone, Elcometrine, and Annovera, is a progestin medication which is used in birth control and in the treatment of endometriosis in the United States, Brazil, and other South American countries.It is available both alone and in combination with an estrogen.It is not effective by mouth and must be given by other routes, most typically as a vaginal ring or implant that is placed into fat.

Side effects of SGA are similar to those of other progestins. SGA is a progestin, or a synthetic progestogen, and hence is an agonist of the progesterone receptor, the biological target of progestogens like progesterone.It has some affinity for the glucocorticoid receptor and has no other important hormonal activity.

SGA was developed by the Population Council and was introduced for medical use by 2000.It is under development in the United States and Europe as a gel in combination with estradiol or testosterone for use as a method of birth control in women and in men, respectively.On August 10, 2018, a first-of-its-kind one-year contraceptive vaginal ring containing segesterone acetate in combination with ethinyl estradiol was approved in the United States.It is marketed under the brand name Annovera and is reusable for up to one year as a method of birth control in women. Annovera does not require refrigeration which is very useful for low resource areas