ノルエルゲストロミン

説明Ortho Evra@ is the first birth control transdermal patch and contains a combination of norelgestromin and ethinylestradiol. The patch can be applied to the buttocks, lower abdomen, upper torso or arms; changed weekly for 3 weeks, followed by a patch-free week. Norelgestromin is the active metabolite produced following oral administration of norgestimate, the progestin component of the contraceptive, Ortho-Cyclen. The half-life value of norelgestromin was approximately 28 h. Following application, norelgestromin rapidly appeared in the serum, reached a plateau by approximately 48h and was maintained at an approximate steady state throughout the wear period. Hepatic metabolites of norelgestromin included norgestrel and various hydroxylated and conjugated metabolites that were eliminated by renal and fecal pathways. Ortho Evra produced ovarian suppression and cycle control. It was significantly more effective in suppressing follicular development than the leading oral contraceptive Triphasil (ethinyl estradiol/levomorgestrel); was as effective in preventing pregnancies and had similar tolerability profile. The patch offers 99% efficacy when used appropriately, as shown by three clinical trials. However, a statistically significantly greater proportion of pregnancies occurred among women weighing 90 kg or more. Ortho Evra was well tolerated, with 2.6% of women discontinuing treatment due to mild to moderate reactions at the site of application. Thus, the patch combined the efficacy of oral contraceptives with the convenience of just once-weekly dosing.