Considering the optimistic results of the SPIRIT 1 study comprising of >1200 females, relugolix was found to be effective to relieve pain associated with endometriosis when used along with estradiol 1 mg and norethindrone acetate 0.5 mg, announced an eminent clinical-stage biopharmaceutical company on June 23, 2020.

Patients were given relugolix 40mg QD plus combination; relugolix 40g QD alone for 12 weeks after relugolix combination for an extra 12 weeks; or placebo. As shown in below table combination of relugolix was linked with clinically significant pain relief as compared to placebo.

At week 24, statistical significant results for all key secondary end points were learnt, comprising of variations in mean dysmenorrhea and pelvic pain, consequences of pain on routine activities via Endometriosis Health Profile-30 (EHP-30) pain domain, many patients not using analgesics and opioids, changes in mean non-menstrual pelvic pain and dyspareunia.

Concerning safety, this combination was well tolerated. Most commonly reported side effects were minimal BMD loss, hot flashes and headache. About 3.8% of patients in the combination therapy withdrew from treatment versus 1.9% in the placebo. Patients who finished the SPIRIT 1 and SPIRIT 2 studies were suitable to register in an extension study to obtain combination therapy for the next 80 weeks. This biopharmaceutical company expects 1-year results from the extension study in the first 4 months of year 2021.