Comparative Pharmacology
Head-to-head clinical analysis: BREVICON 28 DAY versus GENCEPT 10 11 21.
Peer-Reviewed Evidence
Head-to-head clinical analysis: BREVICON 28 DAY versus GENCEPT 10 11 21.
BREVICON 28-DAY vs GENCEPT 10/11-21
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive; ethinyl estradiol and norethindrone suppress gonadotropin secretion (FSH and LH) via negative feedback, inhibiting ovulation. Additionally, alters cervical mucus consistency and endometrial lining to impede sperm penetration and implantation.
GENCEPT 10/11-21 is a combination contraceptive vaginal ring containing ethinyl estradiol and etonogestrel. Ethinyl estradiol is an estrogen that suppresses gonadotropin release, inhibiting ovulation. Etonogestrel is a progestin that thickens cervical mucus, inhibiting sperm penetration, and alters the endometrium.
One tablet (0.5 mg norethindrone and 35 mcg ethinyl estradiol) orally once daily for 28 days (21 active tablets followed by 7 inert tablets).
One tablet (10 mg ethinyl estradiol and 11 mg gestodene on days 1-7, then placebo on days 8-21) orally once daily for 21 days, followed by 7 placebo days.
None Documented
None Documented
Norethindrone: 8-11 hours; Ethinyl estradiol: 13-27 hours; half-life for ethinyl estradiol allows once-daily dosing
Terminal elimination half-life is 24-30 hours; allows once-daily dosing; steady-state achieved in 5-7 days
Renal: ~40% as metabolites and unchanged drug; fecal/biliary: ~60% as metabolites
Renal (30-40% as unchanged drug and metabolites), biliary/fecal (50-60% as metabolites)
Category C
Category C
Oral Contraceptive
Oral Contraceptive