Equivalence of the 3-month and 28-day formulations of triptorelin with regard to achievement and maintenance of medical castration in women with endometriosis

Objective: The present study aims at demonstrating the equivalence of the 28-day and 3-month formulations of triptorelin SR (sustained release) in terms of percentage of patients achieving castration levels of estradiol (≤50 pg/mL) 84 days after treatment initiation. Design: A phase II, prospective, randomized, multicenter, open study was conducted in two parallel groups of women with endometriosis. Setting: Academic hospitals. Patient(s): Seventy-two women with endometriosis. were treated with a single intramuscular injection of 3-month triptorelin SR, and 74 patients were treated with one intramuscular injection of 28-day triptorelin SR every 28 days for 3 months. Intervention(s): As part of two parallel treatment groups, 72 women were given a single intramuscular injection of 3-month triptorelin SR, and 74 women were given one intramuscular injection of 28-day triptorelin SR every 28 days for 3 months. Main Outcome Measure(s): Percentage of patients achieving castration levels of estradiol at the end of the treatment period. Result(s): Patients participated in the study until resumption of menses. Ninety-seven percent of patients given the 3-month formulation and 94% of those given the 28-day formulation were in a state of medical castration on day 84. The mean time to achieve castration was shorter for the 3-month formulation, and the duration of castration was significantly longer. The FSH and LH parameters were comparable, though not always identical. Conclusion(s): The pharmacodynamic effects of the Decapeptyl SR 3-month formulation are equivalent to those of the 28-day formulation. The 3-month formulation provides the added advantage of a longer maintenance of medical castration in women who have endometriosis