The synthetic progestin, an ingredient of the combined contraceptive Qlaira, received EU approval in December for the treatment of endometriosis. It is due to be launched later this year by developer Bayer Schering Pharma, under the trade name Visanne.
Progestogens such as dienogest offer an alternative to GnRH analogues in the management of endometriosis-associated pain. GnRH agonists are an effective treatment for endometriosis, but their oestrogen-suppressing effects can be severe.
The recent trial was an open-label non-inferiority study in 252 women with confirmed endometriosis. Investigators randomised the women to receive dienogest 2mg once daily or leuprorelin acetate 3.75mg every 4 weeks by depot intramuscular injection.
After 24 weeks of treatment, absolute reductions in pelvic pain from baseline, as assessed by visual analogue scale, were comparable in the two groups. Patients receiving dienogest experienced a mean reduction in pain score of 47.5mm whilst those on leuprorelin had a mean reduction of 46.0mm.
Symptoms of oestrogen deprivation, such as hot flushes and suppression of normal monthly bleeding, were reported less frequently in the dienogest group compared with the GnRH group.
Mean lumbar bone mineral density increased slightly in women who received dienogest (+0.25%) but declined markedly in those on leuprorelin (-4.04%).
A 15-month study has shown that the efficacy of dienogest is sustained over time.