Metabolic Profiles in Phase 2 Study of Two 21/7 Oral Contraceptive Regimens (±7 Hormone-Free Days)

Abstract

INTRODUCTION: Metabolic changes observed in women taking combined oral contraceptives may vary depending on the dose and regimen of the combined oral contraceptive components. METHODS: We compared metabolic profiles (secondary endpoints) in women enrolled in a multinational randomized parallel-group open-label study comparing a 21-day combined oral contraceptive regimen containing 150 micrograms desogestrel and 20 micrograms ethinyl estradiol followed by 7 days of 10 micrograms of ethinyl estradiol (Lecette; Treatment 1) compared with a traditional combined oral contraceptive with 7 no treatment (hormone-free) days (Treatment 2). Healthy women aged 18-40 years with regular menstrual cycles and no contraindications to estrogens progestins or both received one of the two combined oral contraceptive regimens for six consecutive 28-day cycles. Serum total cortisol cortisol-binding globulin thyroid-stimulating hormone and sex hormone-binding globulin were measured at baseline and weeks 11 and 23. RESULTS: Of 293 women randomized 246 comprised the per-protocol population (Treatment 1: n=125; Treatment 2: n=121). Mean baseline metabolic parameters were similar for both groups. Increases in mean total cortisol cortisol-binding globulin and sex hormone-binding globulin evident by week 11 were similar with both combined oral contraceptives through week 23. Overall least square mean changes+/-standard errors for Treatments 1 and 2 were 239.0+/-15.7 and 230.8+/-16.0 nmol/L respectively for total cortisol (P=.71) and 40.8+/-1.6 and 37.2+/-1.6 mg/L for cortisol-binding globulin (P=.11); overall sex hormone-binding globulin rose by 163.4+/-7.3 and 149.1+/-7.5 nmol/L (P=.17). Neither group had clinically relevant changes in thyroid-stimulating hormone. CONCLUSIONS: Observed total cortisol cortisol-binding globulin and sex hormone-binding globulin increases in women taking a 21/7 combined oral contraceptive regimen followed by either 7 days of 10 micrograms ethinyl estradiol or 7 hormone-free days were similar.