NEW YORK (Reuters Health) – In a randomized, dose-response trial, a 20-cm-squared transdermal contraceptive patch (Ortho Evra) was as effective as an oral contraceptive, with superior compliance.
Dr. George W. Creasy, of The R. W. Johnson Pharmaceutical Research Institute in Raritan, New Jersey, and colleagues report the finding in the January issue of the American Journal of Obstetrics and Gynecology.
Ortho Evra is the first-ever transdermal hormone patch approved by the US FDA for birth control (see Reuters Health report, November 20, 2001.) The patch, which can be applied to the lower abdomen, buttocks, upper body or upper outer arm, is worn continuously for 7 days before being replaced with a new patch on the same day of the week. The regimen is followed for 3 weeks, with no patch applied in the fourth week.
Dr. Creasy's team evaluated three different patch dose sizes: a 10-cm-squared patch delivering 75 mcg norelgestromin (NGMN) and 10 mcg ethinyl estradiol (EE) daily; a 15-cm-squared patch delivering 112.5 mcg NGMN and 15 mcg EE daily; and a 20-cm-squared patch delivering 150 mcg NGMN and 20 mcg EE daily. They compared these patches with the Ortho-Cyclen oral contraceptive containing 250 mcg norgestimate and 35 mcg EE. A total of 610 healthy women participated.
The 20-cm-squared patch achieved the "protocol-specified criteria for ovulation suppression and cycle control," the researchers report, and was comparable to the oral contraceptive for all pharmacodynamic parameters.
The patches, worn on the lower abdomen for up to four menstrual cycles, were well tolerated with only mild-to-moderate application site reactions reported.
Compliance was significantly better with the patch than the pill. The superior rate of compliance noted in patch wearers, Dr. Creasy and colleagues suggest, may help reduce "typical-use failure rates" which, in the US, are estimated to be as high as 8% with traditional oral contraceptives.
The contraceptive patch represents a "new and innovative method of contraception that may meet the needs of many patients and healthcare professionals," the team concludes.