Segesterone acetate

Segesterone acetate is a steroidal progestin or synthetic progesterone and a 19-norprogesterone derivative with no CH3 group radical in position 6 . In animal studies, segesterone acetate was shown to be one of the most potent progestins . It mediates progestational activity 100 times higher than that of progesterone . It is commonly sold under the brand names Nestorone and Elcometrine and serves as an active component in hormonal contraceptives. It is also used as a treatment for endometriosis in South American countries. Segesterone acetate binds selectively to progesterone receptors and not androgen receptors . Due to its rapid hepatic metabolism, segesterone acetate must be administered parenterally . Segesterone acetate is not an orally active compound, but it is proved to be a potent anti-ovulatory agent when given in implants, vaginal rings or percutaneous gel .

On August 10, 2018, Annovera™ containing segesterone acetate and ethinyl estradiol was granted approval by the U.S. Food and Drug Administration (FDA) as the first and only contraceptive that provides an entire year of protection against unintended pregnancy while entirely under a woman's control. According to the Center for Disease Control, more than 43 million women in the U.S. are at risk of unintended pregnancy, which may be associated with an elevated risk for improper prenatal care, premature and low-birth-weight infants, and physical and mental health risks . The introduction of this new contraceptive method offers an expansion of birth control options for women while maintaining high efficacy and acceptability similar to existing shorter-acting combined hormonal methods . In clinical trials, Annovera™ achieved a 97.3% success in pregnancy prevention . Annovera™ is administered as a vaginal ring that is in place for 21 days and removed for 7 days each cycle. As with other hormonal contraceptives, Annovera™ carries the risk for serious cardiovascular events.

Segesterone acetate in combination with ethinyl estradiol is indicated for use by females of reproductive potential to prevent pregnancy as a combination hormonal contraceptive (CHC). It induces contraception for thirteen 28-day cycles (1 year) following vaginal administration. The vaginal system must remain in place continuously for 3 weeks (21 days) followed by a 1-week (7-day) vaginal system-free interval. The use in females with a body mass index of >29 kg/m^2 has not been adequately evaluated .