[Comparison of transdermal with oral hormone substitution: a multicenter study with a new matrix patch].

166 postmenopausal patients, aged 45-65 years at baseline, with moderate to severe climacteric symptoms were randomly allocated to an open-label, multi-center study which compared the efficacy, safety and acceptance of a transdermal 17 beta-estradiol matrix patch with an oral form of estrogen replacement therapy. In a cyclic sequential regimen, the transdermal system delivered 0.05 mg of estradiol/day. Oral dosages of conjugated equine estrogens were 0.625 mg/day. An oral progestin was also given for 11 days in each cycle for each group. A statistically significant reduction compared to baseline in the primary efficacy parameter, the mean number of hot flashes, occurred with a decrease in each group from 6 per day at baseline to 1 per day at 12 weeks; there was no statistically significant difference between the two groups. The incidence and severity of other postmenopausal symptoms, particularly sweating, difficulty in concentration and palpitations were reduced to a greater extent in the patch group without revealing a significant inter-group difference in the total symptom score. There were also no statistically significant differences in the mean serum estradiol and FSH concentrations between the two treatment groups after 12 weeks of therapy. A similar number of adverse events was observed in both groups. The most frequent adverse events were breast pain and under oral estrogen therapy, gastrointestinal complaints and weight increase. Skin irritation or dermatitis occurred infrequently in the patch group. In summary, the matrix patch represents at least as effective a therapy for postmenopausal symptoms as a standard oral estrogen.