Double-Blind, Placebo-Controlled, Parallel Design, Phase 2 Study to Assess Clinical Activity and Safety of Enobosarm (GTx-024) in Postmenopausal Women With Stress Urinary Incontinence

GTx-024 is an orally bioavailable and tissue-selective nonsteroidal selective androgen receptor modulator (SARM) that has demonstrated androgenic and anabolic activity and is currently being evaluated as a potential treatment for stress urinary incontinence (SUI) in postmenopausal women. Urinary incontinence and pelvic floor disorders are major health problems for women, especially as they age. Pelvic floor muscle relaxation has been found to correlate with lower urinary tract symptoms including SUI. Muscles of the pelvic floor and lower urinary tract are crucial for supporting the pelvic organs and micturition; however, damage to the muscles or lack of hormonal stimulation are thought to contribute to pelvic organ prolapse and urinary incontinence. Although anabolic steroids may increase muscle mass and strength, lack of oral bioavailability and known potential risks have limited their use. Nonsteroidal SARMs have potential to achieve benefits of anabolic steroid therapy (improved muscle mass, cholesterol/triglyceride levels, glucose metabolism, and bone density) with fewer adverse effects, such as hirsutism and acne, in women. Both nonclinical and clinical data suggest that SARMs may provide a new therapeutic option for pelvic floor and lower urinary tract disorders, as both testosterone and its more potent metabolite, dihydrotestosterone, have anabolic effects on muscle.