Comparative Pharmacology
Head-to-head clinical analysis: ORSYTHIA versus ORTHO NOVUM 1 35 28.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORSYTHIA versus ORTHO NOVUM 1 35 28.
ORSYTHIA vs ORTHO-NOVUM 1/35-28
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 oral contraceptive containing ethinyl estradiol and norethindrone. Inhibits ovulation by suppressing gonadotropin release (FSH and LH) from the pituitary; increases viscosity of cervical mucus, impeding sperm penetration; alters endometrial lining, reducing implantation likelihood.
400 mg orally twice daily
1 tablet (norethindrone 1 mg / ethinyl estradiol 35 mcg) orally once daily for 28 consecutive days. Placebo tablets on days 22-28 if included.
None Documented
None Documented
Terminal half-life ~12 hours (range 10-14 h); prolonged in renal impairment (up to 24-30 h).
Norethindrone: 5-14 hrs (terminal); ethinyl estradiol: 10-24 hrs. Steady-state achieved within 5-7 days; terminal half-life supports once-daily dosing.
Primarily renal (≥90% as unchanged drug); <5% biliary/fecal.
Renal 50-60% as metabolites; fecal 30-40% via biliary elimination; <1% unchanged in urine.
Category C
Category C
Hormonal Contraceptive
Hormonal Contraceptive