Reduced pelvic pain in women with endometriosis: efficacy of long-term dienogest treatment

Abstract

Purpose: To investigate the efficacy and safety of dienogest as a long-term treatment in endometriosis, with follow-up after treatment discontinuation. The study included women with endometriosis, who had previously completed a 12-week, placebo-controlled study of dienogest, who participated in an open-label extension study for up to 53 weeks. Thereafter, a patient subgroup was evaluated in a 24-week follow-up after treatment discontinuation.

Methods: A multicenter study performed in Germany, Italy and Ukraine. Women with endometriosis were enrolled at completion of the placebo-controlled study (n = 168). All women received dienogest (2 mg once daily, orally) and changes in pelvic pain (on a visual analog scale), bleeding pattern, adverse events and laboratory parameters were evaluated during and after treatment.

Results: The completion rate among women who entered the open-label extension study was 90.5% (n = 152). A significant decrease in pelvic pain was shown during continued dienogest treatment (P < 0.001). The mean frequency and intensity of bleeding progressively decreased. Adverse events, rated generally mild or moderate, led to withdrawal in four patients (2.4%). No clinically relevant changes in laboratory parameters were observed. During treatment-free follow-up (n = 34), the reduction in pelvic pain persisted, while bleeding frequency and intensity returned to normal patterns.

Conclusions: Long-term dienogest showed a favorable efficacy and safety profile, with progressive decreases in pain and bleeding irregularities during continued treatment; the decrease of pelvic pain persisted for at least 24 weeks after treatment cessation.

Fig. 1

Patient disposition during the extension study and the treatment-free follow-up period

Fig. 2

Mean (±SEM) VAS scores for EAPP during the extension study (FAS) in the total, prior-dienogest and prior-placebo groups. Mean VAS score was statistically significantly reduced by 43.2 (±21.7) mm over the total treatment period of 65 weeks (i.e., placebo-controlled plus extension study; P < 0.001). EAPP endometriosis-associated pain, FAS full analysis set, SEM standard error of the mean, VAS visual analog scale

Fig. 3

Frequencies of maximal intensity of bleeding in 90-day reference periods 1 and 4 during dienogest treatment in the extension study (FAS) FAS full analysis set