Selective progesterone receptor modulators (SPRMs) for uterine fibroids

Area of Science:

• Gynecology and Reproductive Medicine
• Pharmacological Treatments for Benign Tumors
• Evidence-Based Medicine and Clinical Trials

Background:

• Uterine fibroids are benign smooth muscle tumors causing significant symptoms like abnormal bleeding and reproductive dysfunction.
• Selective progesterone receptor modulators (SPRMs) are investigated for fibroid treatment due to progesterone's role in pathogenesis.
• SPRMs may reduce fibroid size and alleviate associated symptoms, with potential for unique, reversible endometrial changes.

Purpose of the Study:

• To evaluate the effectiveness and safety of SPRMs in treating premenopausal women with uterine fibroids.
• To synthesize findings from randomized controlled trials (RCTs) comparing SPRMs against placebo or other treatments.

Main Methods:

• Comprehensive literature search across multiple databases (Cochrane, MEDLINE, Embase, etc.) and clinical trial registries up to May 2016.
• Inclusion of 14 randomized controlled trials (RCTs) involving premenopausal women with fibroids treated for at least three months with an SPRM.
• Independent data extraction and risk of bias assessment, followed by meta-analysis using random-effects models for continuous and dichotomous outcomes.

Main Results:

• SPRM treatment significantly improved fibroid symptom severity and health-related quality of life compared to placebo (moderate-quality evidence).
• SPRMs led to reduced menstrual blood loss and higher amenorrhea rates versus placebo, though endometrial changes were more frequent (low-quality evidence).
• Compared to leuprolide acetate, SPRMs showed no significant difference in quality of life or bleeding symptom improvements, but endometrial changes were more common.

Conclusions:

• Short-term SPRM use effectively improves quality of life and reduces bleeding in women with symptomatic fibroids.
• SPRMs demonstrate comparable effectiveness to leuprolide acetate for quality of life and bleeding symptoms.
• SPRMs are associated with benign, reversible endometrial changes; further well-designed comparative trials are needed.