Comparative Pharmacology
Head-to-head clinical analysis: ORSYTHIA versus ORTHO NOVUM 1 35 21.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORSYTHIA versus ORTHO NOVUM 1 35 21.
ORSYTHIA vs ORTHO-NOVUM 1/35-21
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Nonsteroidal aromatase inhibitor that selectively and reversibly inhibits aromatase, the enzyme responsible for converting androgens to estrogens, thereby reducing estrogen levels in tissues.
Combination estrogen-progestin contraceptive; suppresses gonadotropin (FSH and LH) secretion via negative feedback, inhibiting ovulation. Increases cervical mucus viscosity and alters endometrial lining, impairing sperm penetration and implantation.
400 mg orally twice daily
One tablet orally once daily for 21 days, followed by 7 placebo tablets. Each tablet contains 1 mg norethindrone and 0.035 mg ethinyl estradiol.
None Documented
None Documented
Terminal half-life ~12 hours (range 10-14 h); prolonged in renal impairment (up to 24-30 h).
Norethindrone: 7-9 hours (terminal); Ethinyl estradiol: 13-27 hours (terminal). At steady state, clinical contraceptive efficacy is maintained with daily dosing.
Primarily renal (≥90% as unchanged drug); <5% biliary/fecal.
Renal (approx. 40% as metabolites, <10% unchanged), fecal (approx. 60% as metabolites, primarily via bile).
Category C
Category C
Hormonal Contraceptive
Hormonal Contraceptive