Comparative Pharmacology
Head-to-head clinical analysis: ORSYTHIA versus ORTHO CYCLEN 28.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORSYTHIA versus ORTHO CYCLEN 28.
ORSYTHIA vs ORTHO CYCLEN-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 norgestimate. The primary mechanism is inhibition of gonadotropin secretion (FSH and LH) via negative feedback on the hypothalamic-pituitary axis, thereby suppressing ovulation. Additional effects include thickening of cervical mucus (impedes sperm penetration) and alterations in the endometrium (reduces implantation likelihood).
400 mg orally twice daily
One tablet (0.18 mg norgestimate/0.035 mg ethinyl estradiol) orally once daily for 28 days, first tablet on day 1 of menstrual cycle with 7 placebo tablets in last 7 days.
None Documented
None Documented
Terminal half-life ~12 hours (range 10-14 h); prolonged in renal impairment (up to 24-30 h).
Ethinyl estradiol: 13-27 hours; Norelgestromin (active metabolite of norgestimate): 28-52 hours. Terminal half-lives support once-daily dosing.
Primarily renal (≥90% as unchanged drug); <5% biliary/fecal.
Renal (60-70% as metabolites, ~20% unchanged), Fecal (30-40% as metabolites); primarily conjugated metabolites of ethinyl estradiol and norgestimate.
Category C
Category C
Hormonal Contraceptive
Hormonal Contraceptive