Objective: To evaluate the efficacy and safety of an ascending-dose, extended-regimen (ADER) combined oral contraceptive consisting of levonorgestrel (LNG) 150 mcg/ethinyl estradiol (EE) 20 mcg for 42 days, LNG 150 mcg/EE 25 mcg for 21 days, LNG 150 mcg/EE 30 mcg for 21 days and EE 10 mcg for 7 days.
Study design: This was a multicenter, open-label, phase 3, single-arm study. Sexually active women aged 18-40 years were enrolled and received ADER for up to 1 year (4 consecutive 91-day cycles). Participants kept diaries to record adherence, bleeding/spotting and other contraceptive use. Efficacy was measured using the Pearl Index and the life-table method; safety and tolerability were assessed through reported adverse events (AEs).
Results: A total of 3701 women were enrolled and 2144 completed the study. The Pearl Index was 3.19 [95% confidence interval (CI), 2.49-4.03], based on 70 pregnancies that occurred after ADER initiation and ≤ 7 days after the last LNG/EE or EE-only pill in women aged 18-35 years, excluding cycles in which another contraceptive method was used. Life-table pregnancy rate was 2.82% (95% CI, 2.23%-3.57%) for all users aged 18-35 years. Unscheduled bleeding/spotting decreased with increasing EE doses within each cycle and decreased after cycle 1. No unexpected AEs or changes in laboratory parameters were reported.
Conclusion: This study demonstrated that ADER effectively prevented pregnancy with a favorable safety and tolerability profile.
Trial registration: ClinicalTrials.gov NCT00996580.
Keywords: Bleeding; Contraception; Low dose; Spotting.
Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.