Comparative Pharmacology
Head-to-head clinical analysis: CYCLAFEM 7 7 7 versus ZOVIA 1 35E 28.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CYCLAFEM 7 7 7 versus ZOVIA 1 35E 28.
CYCLAFEM 7/7/7 vs ZOVIA 1/35E-28
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination estrogen-progestin contraceptive. Ethinyl estradiol suppresses gonadotropin release (FSH, LH) via negative feedback on hypothalamic-pituitary axis; norethindrone induces endometrial changes that inhibit implantation and thickens cervical mucus.
ZOVIA 1/35E-28 is a combined oral contraceptive (COC) containing ethinyl estradiol and norethindrone. It inhibits ovulation via suppression of gonadotropins (FSH and LH), increases cervical mucus viscosity, and alters endometrial receptivity.
One tablet (norethindrone 0.5 mg/ethinyl estradiol 35 mcg) orally once daily for 7 days, then one tablet (norethindrone 0.75 mg/ethinyl estradiol 35 mcg) orally once daily for 7 days, then one tablet (norethindrone 1 mg/ethinyl estradiol 35 mcg) orally once daily for 7 days. Dispensed in a 21-tablet pack with 7 placebo tablets. For contraception, take one tablet daily at same time each day for 28 days; begin next pack after 28-day cycle.
One tablet orally once daily at the same time each day for 21 days, followed by 7 days of placebo (inactive tablets), then repeat.
None Documented
None Documented
Terminal half-life: 5-13 hours (mean 8 hrs); clinical context: supports every-28-day dosing interval for intramuscular depot.
Ethinyl estradiol: ~17 hours (range 13-27 hours); Norethindrone: ~8 hours (range 5-14 hours). Clinical context: Steady state achieved in ~5-7 days; contraceptive effect requires consistent dosing.
Renal: ~50-60% as conjugated metabolites; Fecal: ~30-40% via bile; <1% unchanged.
Renal: ~40% as metabolites; biliary/fecal: ~40% as metabolites; unchanged drug minimal (<1%).
Category C
Category C
Oral Contraceptive
Oral Contraceptive