Prospective randomized double-blind trial of 3 versus 6 months of nafarelin therapy for endometriosis associated pelvic pain

Objectives: To determine the effectiveness of a 3-month course of nafarelin and, furthermore, to determine the long-term efficacy in patients treated for 3 and 6 months with nafarelin for symptoms associated with endometriosis. Design: Double-blind, prospective, multicenter, clinical trial. Setting: Fifteen reproductive endocrine clinics throughout the United States. Patients: One hundred seventy-nine women with pelvic pain and endometriosis. Interventions: Patients were assigned randomly to 3 months nafarelin followed by 3 months of placebo (n = 91) or to 6 months nafarelin (n = 88) in a prospective, randomized, double-blind multicenter trial. Patients were followed for 12 months after cessation of therapy. Main Outcome Measures: Patient-reported pain scores and physician-reported physical exam findings. Results: Pain scores dropped significantly by the end of treatment in both groups. Symptoms recurred in both groups, and pain scores gradually increased during the follow-up period but always remained below baseline in both groups. No significant difference in efficacy was noted between the groups. A total of 26% of patients in each group underwent retreatment for recurrent symptoms. Conclusions: A 3-month course of nafarelin provided effective symptom relief for endometriosis. One year follow-up demonstrated continued pain relief but with gradual return of symptoms.