Linzagolix: a new GnRH-antagonist under investigation for the treatment of endometriosis and uterine myomas

Introduction: Uterine myomas and endometriosis are benign hormone-dependent diseases affecting women of reproductive age. Substantial efforts have been made to develop innovative medical options for treating these gynecologic diseases. Elagolix and relugolix have been approved in some countries for treating endometriosis and myomas, respectively; however, linzagolix (OBE 2109, KLH 2109) is a new oral gonadotropin-releasing hormone (GnRH) antagonist in phase II–III trials. Treatment options for women with contraindications for hormonal therapies or who refuse particular options, are the driving force behind the development of new drugs in this area. Area covered: This drug evaluation highlights definitive and preliminary results from previous and ongoing studies of linzagolix for the treatment of endometriosis and myomas. Expert opinion: Linzagolix showed a dose-dependent and rapidly reversible action on the pituitary-gonadal axis. In a recent phase II trial (EDELWEISS), linzagolix significantly reduced pain related to endometriosis and improved quality of life at single daily doses of 75–200 mg. The preliminary results of international, double-blind phase III trials (PRIMROSE 1 and 2) reported its efficacy in treating heavy menstrual bleeding related to myomas with a good safety profile. Further studies will determine the necessity of add-back therapy during long-term use of linzagolix.