SUFU 2018: Oral Enobosarm Shows Promising Activity in Post-Menopausal Women with Stress Urinary Incontinence: Results of a Phase 2 Study

Austin, TX ( Dr. Kenneth M Peters and colleagues presented the results from the single-arm, open-label Phase 2 clinical trial evaluating enobosarm in postmenopausal women with stress urinary incontinence (SUI). The first clinical trial to evaluate an orally-administered selective androgen receptor modulator (SARM) for SUI.  Enobosarm, which is an oral selective androgen receptor modulator, given as an androgenic agent to modulate the pelvic floor and urinary sphincter was given to 17 post-menopausal women with stress predominant urinary incontinence were given the drug for 12 weeks.  The primary endpoint was the number of stress incontinence episodes per day on the 3−day voiding diary. Secondary endpoints include pad weights, BST, and quality of life (QOL) instruments (MESA, PGI−S, PGI−I, UDI−6, IIQ−7, and FSFI). Follow up was up to 40 weeks. 

The authors found that all patients experienced a greater than 50% decrease in the average number of reported stress leaks per day. At 12 weeks, stress leaks per day decreased by 83%.  6/17 women had a negative bladder stress test at 12 weeks and pad weights decreased by >70%. All QOL scores improved at 12 weeks.  The median FSFI score increased from 15.9 to 28.05 and MESA−stress score fell from 81 to 41. There were no serious adverse events reported. 

The authors note that in addition, there was an improvement in sexual function, which is promising for the potential future for this drug. The authors evaluated the endometrial stripe with MRI; obtaining these images, they were able to delineate pelvic floor anatomy better.  Post treatment MRI demonstrated results in support of this drug as well.  The authors advocate that enobosarm is a safe and tolerable drug.  This is the first study to assess role of a SARM for SUI.  ASTRID (Assessing Enobosarm for Stress Urinary Incontinence Disorder), a Phase 2 placebo controlled clinical trial to further investigate safety and efficacy is ongoing now.

Study funded by GTx

Presented by: Kenneth M. Peters, MD¹

Co-Authors: Diane Newman DNP², Laurence Belkoff DO³, Kiran Nandalur MD¹, Mary Ann Johnston PharmD⁴, Susan Small RPh⁴, Ryan Taylor PhD⁴ and Larry Sirls MD¹
Author Information:
1. Professor and Chairman of Urology Oakland University William Beaumont School of Medicine, Rochester, MI
2. University of Pennsylvania, Philadelphia, PA
3. Urological Consultants of SEPA, Bala Cynwyd, PA
4. GTx, Inc.,Memphis, TN

Written by: Cristina Palmer, DO. Female Urology, Pelvic Reconstruction, Voiding Dysfunction Fellow, Department of Urology, UC Irvine Medical Center, Orange, California at the Society of Urodynamics, Female Pelvic Medicine & Urogenital Reconstruction Winter Meeting (SUFU 2018), February 27-March 3, 2018, Austin, Texas