Comparative Pharmacology
Head-to-head clinical analysis: GENCEPT 10 11 21 versus HAILEY FE 1 5 30.
Peer-Reviewed Evidence
Head-to-head clinical analysis: GENCEPT 10 11 21 versus HAILEY FE 1 5 30.
GENCEPT 10/11-21 vs HAILEY FE 1.5/30
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Combination estrogen-progestin contraceptive that suppresses gonadotropin release (FSH and LH) from the pituitary, inhibiting ovulation. Additionally, increases viscosity of cervical mucus and alters endometrial receptivity.
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.
One tablet orally once daily for 21 consecutive days, followed by 7 days of placebo tablets.
None Documented
None Documented
Terminal elimination half-life is 24-30 hours; allows once-daily dosing; steady-state achieved in 5-7 days
Ethinyl estradiol: terminal half-life ~17-24 hours; norethindrone: terminal half-life ~5-14 hours (mean 11 hours). The clinical significance is that steady-state is reached within 5-7 days.
Renal (30-40% as unchanged drug and metabolites), biliary/fecal (50-60% as metabolites)
Ethinyl estradiol is primarily excreted renally (40-45%) and via bile/feces (45-55%). Norethindrone is excreted 50-60% renally and 30-40% fecally.
Category C
Category C
Oral Contraceptive
Oral Contraceptive