Experimental Drug Improves Muscle Strength in Cancer

HOUSTON  – An experimental drug significantly improved physical function in men with cancer-related muscle wasting, compared with placebo – and more so in the men with low testosterone levels – in a secondary analysis of a randomized, double-blind, phase II clinical trial.

In all, 60% of the 93 men for whom baseline testosterone levels were available had hypogonadism when the patients were randomized to treatment with daily placebo or 1 mg or 3 mg of enobosarm for 16 weeks. Before treatment, the eugonadal males showed significantly better physical function, as measured by stair-climb power, compared with the hypogonadal patients (174 W vs. 147 W). Lower testosterone levels correlated with lower physical function.

Enobosarm significantly improved physical function (a secondary end point in the trial) with an average 17% increase in stair-climb power in hypogonadal men, and a 12% increase in power in eugonadal men, compared with baseline, Dr. Adrian Dobs and her associates reported at the annual meeting of the Endocrine Society.

Among men on placebo, stair-climb power increased by about 10% in hypogonadal men and by roughly 1% in eugonadal men, compared with baseline, but the changes were not statistically significant, said Dr. Dobs, professor of medicine and oncology at Johns Hopkins University, Baltimore.

Adverse events included fatigue in 21% of both treatment groups, anemia in 19% of those on enobosarm and 15% in those on placebo, nausea in 18% on enobosarm and 14% on placebo, diarrhea in 16% on enobosarm and 14% on placebo, vomiting in 12% of each treatment group, weight decrease in 12% on enobosarm and 10% on placebo, and constipation in 14% on enobosarm and 4% on placebo.

The investigators defined hypogonadism as a testosterone level below 300 ng/dL.

Enobosarm is a nonsteroidal SARM (selective androgen receptor modulator) that produces anabolic effects in bone and muscle without causing the prostate effects in men or hair growth in women that is seen with steroids.

The analysis used data from a larger trial in 159 people with cancer (65% of whom were men) who had lost at least 2% (and an average of 8%) of their weight in the previous 6 months. The men were older than 45 years of age, the women were postmenopausal, and each had a body mass index less than 35 mg/kg².

The multicenter study as a whole met its primary end point of increasing lean body mass (muscle) and its secondary end point of improving physical function, Dr. Dobs said in an interview. Those results were reported on the website of the company that is developing the drug, GTx Inc., and at previous medical meetings, according to an interview in the Los Angeles Times.

Dr. Dobs did not report results for lean body mass in the current analysis based on gonadal status.

Cancer diagnoses included colorectal cancer, non–small cell lung cancer, non-Hodgkin’s lymphoma, chronic lymphocytic leukemia, and breast cancer. Patients participated in the study prior to or between courses of chemotherapy. Rates of hypogonadism were similar for each type of cancer. Patients with hypogonadism were less likely to complete the study than were eugonadal men.

Patients with cancer develop cachexia (muscle wasting) because of reduced anabolic activity, increased catabolic activity, or both, accounting for a progressive catabolic state. Up to 50% of patients with lung cancer show severe cachexia at the time of diagnosis, and the muscle wasting increases throughout the course of the malignancy, Dr. Dobs said.

Two phase III clinical trials are underway to study effects of 3 mg/day of enobosarm for the prevention and treatment of muscle wasting in patients with non–small cell lung cancer.

GTx Inc., the company that is developing enobosarm, funded the current study. Dr. Dobs reported having no other financial disclosures.

HOUSTON  – An experimental drug significantly improved physical function in men with cancer-related muscle wasting, compared with placebo – and more so in the men with low testosterone levels – in a secondary analysis of a randomized, double-blind, phase II clinical trial.

In all, 60% of the 93 men for whom baseline testosterone levels were available had hypogonadism when the patients were randomized to treatment with daily placebo or 1 mg or 3 mg of enobosarm for 16 weeks. Before treatment, the eugonadal males showed significantly better physical function, as measured by stair-climb power, compared with the hypogonadal patients (174 W vs. 147 W). Lower testosterone levels correlated with lower physical function.

Enobosarm significantly improved physical function (a secondary end point in the trial) with an average 17% increase in stair-climb power in hypogonadal men, and a 12% increase in power in eugonadal men, compared with baseline, Dr. Adrian Dobs and her associates reported at the annual meeting of the Endocrine Society.

Among men on placebo, stair-climb power increased by about 10% in hypogonadal men and by roughly 1% in eugonadal men, compared with baseline, but the changes were not statistically significant, said Dr. Dobs, professor of medicine and oncology at Johns Hopkins University, Baltimore.

Adverse events included fatigue in 21% of both treatment groups, anemia in 19% of those on enobosarm and 15% in those on placebo, nausea in 18% on enobosarm and 14% on placebo, diarrhea in 16% on enobosarm and 14% on placebo, vomiting in 12% of each treatment group, weight decrease in 12% on enobosarm and 10% on placebo, and constipation in 14% on enobosarm and 4% on placebo.

The investigators defined hypogonadism as a testosterone level below 300 ng/dL.

Enobosarm is a nonsteroidal SARM (selective androgen receptor modulator) that produces anabolic effects in bone and muscle without causing the prostate effects in men or hair growth in women that is seen with steroids.

The analysis used data from a larger trial in 159 people with cancer (65% of whom were men) who had lost at least 2% (and an average of 8%) of their weight in the previous 6 months. The men were older than 45 years of age, the women were postmenopausal, and each had a body mass index less than 35 mg/kg².

The multicenter study as a whole met its primary end point of increasing lean body mass (muscle) and its secondary end point of improving physical function, Dr. Dobs said in an interview. Those results were reported on the website of the company that is developing the drug, GTx Inc., and at previous medical meetings, according to an interview in the Los Angeles Times.

Dr. Dobs did not report results for lean body mass in the current analysis based on gonadal status.

Cancer diagnoses included colorectal cancer, non–small cell lung cancer, non-Hodgkin’s lymphoma, chronic lymphocytic leukemia, and breast cancer. Patients participated in the study prior to or between courses of chemotherapy. Rates of hypogonadism were similar for each type of cancer. Patients with hypogonadism were less likely to complete the study than were eugonadal men.

Patients with cancer develop cachexia (muscle wasting) because of reduced anabolic activity, increased catabolic activity, or both, accounting for a progressive catabolic state. Up to 50% of patients with lung cancer show severe cachexia at the time of diagnosis, and the muscle wasting increases throughout the course of the malignancy, Dr. Dobs said.

Two phase III clinical trials are underway to study effects of 3 mg/day of enobosarm for the prevention and treatment of muscle wasting in patients with non–small cell lung cancer.

GTx Inc., the company that is developing enobosarm, funded the current study. Dr. Dobs reported having no other financial disclosures.

HOUSTON  – An experimental drug significantly improved physical function in men with cancer-related muscle wasting, compared with placebo – and more so in the men with low testosterone levels – in a secondary analysis of a randomized, double-blind, phase II clinical trial.

In all, 60% of the 93 men for whom baseline testosterone levels were available had hypogonadism when the patients were randomized to treatment with daily placebo or 1 mg or 3 mg of enobosarm for 16 weeks. Before treatment, the eugonadal males showed significantly better physical function, as measured by stair-climb power, compared with the hypogonadal patients (174 W vs. 147 W). Lower testosterone levels correlated with lower physical function.

Enobosarm significantly improved physical function (a secondary end point in the trial) with an average 17% increase in stair-climb power in hypogonadal men, and a 12% increase in power in eugonadal men, compared with baseline, Dr. Adrian Dobs and her associates reported at the annual meeting of the Endocrine Society.

Among men on placebo, stair-climb power increased by about 10% in hypogonadal men and by roughly 1% in eugonadal men, compared with baseline, but the changes were not statistically significant, said Dr. Dobs, professor of medicine and oncology at Johns Hopkins University, Baltimore.

Adverse events included fatigue in 21% of both treatment groups, anemia in 19% of those on enobosarm and 15% in those on placebo, nausea in 18% on enobosarm and 14% on placebo, diarrhea in 16% on enobosarm and 14% on placebo, vomiting in 12% of each treatment group, weight decrease in 12% on enobosarm and 10% on placebo, and constipation in 14% on enobosarm and 4% on placebo.

The investigators defined hypogonadism as a testosterone level below 300 ng/dL.

Enobosarm is a nonsteroidal SARM (selective androgen receptor modulator) that produces anabolic effects in bone and muscle without causing the prostate effects in men or hair growth in women that is seen with steroids.

The analysis used data from a larger trial in 159 people with cancer (65% of whom were men) who had lost at least 2% (and an average of 8%) of their weight in the previous 6 months. The men were older than 45 years of age, the women were postmenopausal, and each had a body mass index less than 35 mg/kg².

The multicenter study as a whole met its primary end point of increasing lean body mass (muscle) and its secondary end point of improving physical function, Dr. Dobs said in an interview. Those results were reported on the website of the company that is developing the drug, GTx Inc., and at previous medical meetings, according to an interview in the Los Angeles Times.

Dr. Dobs did not report results for lean body mass in the current analysis based on gonadal status.

Cancer diagnoses included colorectal cancer, non–small cell lung cancer, non-Hodgkin’s lymphoma, chronic lymphocytic leukemia, and breast cancer. Patients participated in the study prior to or between courses of chemotherapy. Rates of hypogonadism were similar for each type of cancer. Patients with hypogonadism were less likely to complete the study than were eugonadal men.

Patients with cancer develop cachexia (muscle wasting) because of reduced anabolic activity, increased catabolic activity, or both, accounting for a progressive catabolic state. Up to 50% of patients with lung cancer show severe cachexia at the time of diagnosis, and the muscle wasting increases throughout the course of the malignancy, Dr. Dobs said.

Two phase III clinical trials are underway to study effects of 3 mg/day of enobosarm for the prevention and treatment of muscle wasting in patients with non–small cell lung cancer.

GTx Inc., the company that is developing enobosarm, funded the current study. Dr. Dobs reported having no other financial disclosures.