Comparative Pharmacology
Head-to-head clinical analysis: ANNOVERA versus SEASONALE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ANNOVERA versus SEASONALE.
ANNOVERA vs SEASONALE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination hormonal contraceptive containing segesterone acetate, a progestin, and ethinyl estradiol, an estrogen. Segesterone acetate suppresses gonadotropin release, preventing ovulation; ethinyl estradiol contributes to contraceptive efficacy by stabilizing the endometrium and inhibiting gonadotropin secretion.
Seasonale is a combination oral contraceptive containing ethinyl estradiol and levonorgestrel. It suppresses gonadotropin release, inhibiting ovulation, and alters cervical mucus to reduce sperm penetration and endometrial lining to reduce implantation.
One vaginal ring inserted and left in place for 3 weeks, followed by a 1-week ring-free interval. Each ring releases ethinyl estradiol 0.024 mg/day and segesterone acetate 0.15 mg/day over 21 days.
One tablet (0.03 mg ethinyl estradiol and 0.15 mg levonorgestrel) orally once daily for 84 consecutive days, followed by 7 days of placebo.
None Documented
None Documented
Terminal half-life of etonogestrel (ENG): ~25 hours; ethinylestradiol (EE): ~12 hours; steady-state achieved after 7-14 days.
Ethinyl estradiol: terminal half-life 13-27 hours (mean 17 hours); levonorgestrel: terminal half-life 11-45 hours (mean 25 hours). Clinical context: Supports once-daily dosing; steady-state achieved within 5-10 days.
Renal: ~60% as metabolites; fecal: ~35% as metabolites; biliary: minor.
Renal excretion of metabolites (approximately 50-60% as glucuronide and sulfate conjugates of ethinyl estradiol and levonorgestrel) and fecal elimination (approximately 40-50%).
Category C
Category C
Contraceptive
Contraceptive, Combination Hormonal