Evaluation of a continuous regimen of levonorgestrel/ethinyl estradiol: phase 3 study results

OBJECTIVE: This study was conducted to evaluate the safety and efficacy of a continuous daily regimen of levonorgestrel (LNG) 90 microg/ethinyl estradiol (EE) 20 microg (continuous LNG/EE). METHODS: Healthy women aged 18-49 years with regular menstrual cycles for 3 months enrolled in this single-treatment open-label study and took one pill of LNG 90 microg/EE 20 microg daily for 12 months. RESULTS: For the 2134 subjects enrolled, the Pearl Index method failure was 1.26, and user failure was 0.34. While on Pill Pack 13, 58.7% of subjects reported amenorrhea and 79.0% reported absence of bleeding. Overall, the number of bleeding and spotting days per pill pack declined progressively. Adverse events and discontinuations were comparable to those reported for cyclic oral contraceptive (OC) regimens, except for higher rates in those related to uterine bleeding. CONCLUSIONS: Continuous LNG/EE demonstrated a good safety profile and efficacy similar to cyclic OCs. The regimen continuously inhibited menses, increased the incidence of amenorrhea over time and, except for a subset of women, decreased the number of bleeding and spotting days.