A Plain Language Summary to Learn About Relugolix Combination Therapy for the Treatment of Pain Associated with Endometriosis

Abstract

What is this summary about?

This is a summary of research studies (known as clinical trials) called SPIRIT 1 and SPIRIT 2. The SPIRIT 1 and SPIRIT 2 studies compared how well a medicine called relugolix combination therapy worked in relieving pain in women with moderate to severe endometriosis compared to a placebo, a pill with no active medication. Endometriosis occurs when tissue similar to what normally lines the uterus grows in other places, such as the ovaries, fallopian tubes, and bowels.

What were the results?

Researchers looked at 1261 adult women with moderate to severe endometriosis. Randomly, 420 (33%) of these women were assigned to relugolix combination therapy, 420 (33%) were assigned to delayed relugolix combination therapy (relugolix alone first and then relugolix combination therapy for the remainder of the study), and 421 (33%) were assigned to placebo. The SPIRIT 1 and SPIRIT 2 studies showed that more women taking relugolix combination therapy (75% from SPIRIT 1 and 75% from SPIRIT 2) for 24 weeks had both less pelvic or groin pain during menstrual periods from endometriosis and no need for more pain medicines than women who took placebo (27% from SPIRIT 1 and 30% from SPIRIT 2). The SPIRIT 1 and SPIRIT 2 studies also showed that more women taking relugolix combination therapy (59% from SPIRIT 1 and 66% from SPIRIT 2) for 24 weeks had both less pelvic or groin pain between menstrual periods from endometriosis and no need for more pain medicines than women who took placebo (40% from SPIRIT 1 and 43% from SPIRIT 2). Women taking relugolix combination therapy had less pelvic or groin pain during and between menstrual periods within 4 weeks of starting the medicine. The most common side effects were headaches, the common cold, and hot flushes or feeling hot among women taking relugolix combination therapy, delayed relugolix combination therapy, and placebo. Relugolix combination therapy was considered safe for those with no major medical problems. Women taking relugolix combination therapy had little to no loss of bone mineral density (a way of knowing how strong bones are) after 24 weeks of treatment.

What do the results of these studies tell us?

Women with moderate to severe endometriosis taking relugolix combination therapy had much less pain from endometriosis than women taking placebo.

Clinical Trial Registration: NCT03204318 (SPIRIT-1); NCT03204331 (SPIRIT-2) (ClinicalTrials.gov)

This is an abstract of the Plain Language Summary of Publication article.

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Link to original article here

Keywords::

• endometriosis
• relugolix
• relugolix combination therapy
• SPIRIT trials

Acknowledgments

Myovant Sciences GmbH and the authors thank all the women who took part in these studies and their families, as well as the treating physicians, research nurses, study coordinators, and operations staff. We thank Slava Rakov for his contributions to study recruitment and critical review of the manuscript and So Jung Imm for her contributions to data preparation and analysis. We also thank Eric Brown and Qurratul Ann Warsi for all their contributions toward the original manuscript.

Financial disclosure

LCG reports personal fees from Myovant Sciences. SA-S reports personal fees from Myovant Sciences, Bayer, Abbvie, and UpToDate. CMB reports fees from Myovant Sciences and ObsEva, grants from Bayer Healthcare, and role of Chair of ESHRE Endometriosis Guideline Group. BAL reports personal fees from Myovant Sciences. NPJ reports personal fees from Myovant Sciences during the conduct of the study and personal fees from Guerbet, Abbott, and Roche Diagnostrics. The authors did not receive compensation for manuscript writing, review, and revision. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Competing interests disclosure

JCAF, YL, and RBW are employees and shareholders of Myovant Sciences. VM is a consultant to Myovant Sciences. The authors have no other competing interests or relevant affiliations with any organization or entity with the subject matter or materials discussed in the manuscript apart from those disclosed. The SPIRIT 1 and SPIRIT 2 studies were sponsored by Sumitomo Pharma Switzerland GmbH (Aeschengraben 27, 4051 Basel, Switzerland; [phone]) Myfembree (a combination tablet containing relugolix, estradiol, and norethindrone acetate) is jointly developed by Sumitomo Pharma Switzerland GmbH and Pfizer Inc.

Writing disclosure

Writing support for this summary was provided by Anna Stern, PhD, of ICON (Blue Bell, PA) and was funded by Sumitomo Pharma Switzerland GmbH in partnership with Pfizer Inc.