(ChemotherapyAdvisor) – The oral selective androgen receptor modulator enobosarm—the first in a new class of agents—improved physical function in men who were both hypogonadal and eugonadal, according to results of a randomized phase 2b study of the effect of the agent on cancer cachexia presented at The Endocrine Society’s 94th Annual Meeting in Houston, TX, June 24.
Hypogonadism is common in patients with cancer and is associated with cachexia and poor outcomes. “Up to 50% of males with advanced cancer are hypogonadal at presentation or during the course of treatment,” noted lead study author Adrian S. Dobs, MD, MHS, of Johns Hopkins University School of Medicine, Baltimore, MD.
The study enrolled males >45 years of age or postmenopausal females with ≥2% weight loss in the 6 months prior to randomization, BMI <35, and either non–small-cell lung cancer, colorectal cancer, non-Hodgkin’s lymphoma, chronic lymphocytic leukemia, or breast cancer. The multicenter study randomly assigned patients to oral enobosarm 1mg or 3mg or placebo daily for 16 weeks.
Initial results from the larger study, which were previously reported, included 159 patients with cancer; 65% were men. This study presented results on incidence and impact of hypogonadism (T<300ng/dL) in the subset of 93 male patients for whom baseline testosterone levels were available; 60% were hypogonadal at randomization.
Baseline testosterone levels were positively correlated with weight loss (r=0.32, P=0.002) with hypogonadal men demonstrating greater weight loss in the previous 6 months (median -9.5%). Baseline physical function, as measured by stair climb power, was higher among eugonadal males compared to hypogonadal males (84.5 watts vs 70.6 watts; P=0.016).
Enobosarm was found to improve physical function regardless of baseline gonadal status (hypogonadal: 18.7%, P=0.0061; eugonadal: 13.2%, P=0.0032). Magnitude of improvement was greater in hypogonadal men, the investigators reported.
According to Dr. Dobs, this study has laid the groundwork for ongoing research examining the effect of enobosarm on cachexia; specifically, among patients with lung cancer.
“Enobosarm has the potential to improve physical performance and increase muscle mass, potentially providing lung cancer patients with improved strength, or physical function, more independence, increased quality of life, better response to chemotherapy, and hopefully longer survival,” she said.
The study was funded by GTx, Inc., Memphis, TN.
Abstract (requires free registration; search for “Dobs” in box at top left)