Uterine fibroids are noncancerous tumours that grow in the uterus and can cause heavy menstrual bleeding, pelvic pain and blood clots. Hysterectomy is the only definitive treatment, but less invasive procedures and medical treatments are available. The oral gonadotropin-releasing hormone receptor antagonist relugolix, which suppresses ovarian hormone levels, significantly reduced menstrual bleeding in clinical trials and also improved other symptoms in patients with uterine fibroids. It has now been approved in combination with estradiol and norethisterone acetate (Ryeqo; Myfembree) as a fixed-dose tablet for treating uterine fibroids associated with heavy menstrual bleeding and other debilitating symptoms.
In the parent trials, relugolix CT was associated with a higher responder rate compared to placebo, and in the extension study, relugolix CT was also associated with sustained improvements in symptom severity and fibroid-related quality of life, as measured by changes from baseline on the Uterine Fibroid Symptom & Health-Related Quality of Life Questionnaire. In addition, relugolix CT was shown to be noninferior to leuprolide in terms of the number of patients who achieved anaemia.
Relugolix was well-tolerated, and the incidence of adverse events was similar between relugolix CT and leuprolide. The most common event was hot flashes (54% vs 51%), followed by fatigue (21% vs 21%) and constipation (16% vs 18%). Diarrhea was reported in a greater proportion of patients receiving relugolix CT than leuprolide (12% vs 6%), but most cases were mild or moderate and did not lead to treatment withdrawal. The increase in levels of hepatic aminotransferases was also observed in both groups, but the rates were higher with relugolix CT, and no patient was withdrawn because of increased hepatic enzymes.
Serious side effects associated with relugolix include severe heart symptoms (fast, irregular or pounding heartbeat; fluttering in your chest; shortness of breath); liver problems (abnormal liver function tests including high levels of certain liver enzymes); and a severe allergic reaction that may be fatal (hives; difficult breathing; swelling of the face, lips, tongue, or throat). Tell your doctor if you have any of these symptoms. Also report any other serious side effects, especially if they are new or worsened.
Take relugolix exactly as prescribed by your doctor, and do not take more or less than it is directed on the label. It is important to take relugolix at the same time each day for best results.
Ask your doctor about taking relugolix with other medications, including vitamins and herbs. Some medicines can interact with relugolix, and some can affect how it works or increase your risk for serious side effects. Keep a list of all your medicines (including prescription and nonprescription drugs) and share it with your doctor and pharmacist.
Relugolix can pass into breast milk. Do not breast-feed while taking this medication. Women who become pregnant should not handle or breathe in the dust from relugolix tablets. It can harm an unborn baby. Use effective birth control, and tell your doctor if you think you are pregnant or might become pregnant.
