Acorda’s GGF2 can improve erectile function after cavernous nerve damage

Acorda Therapeutics, Inc. (Nasdaq: ACOR) announced data from a preclinical study showed that treatment with Glial Growth Factor 2 (GGF2) improved erectile function in an animal model following a cavernous nerve (CN) injury, a common complication of prostate surgery. These data were featured in a platform presentation at the ISSM/SMSNA World Meeting on Sexual Medicine in Chicago, IL.    

Approximately 270,000 prostate surgeries are performed in the United States annually. The vast majority of those surgeries are to treat prostate cancer and prostate enlargement (benign prostatic hyperplasia, or BPH). The National Cancer Institute estimates that approximately 120,000 men in the U.S. diagnosed with prostate cancer in 2012 will have surgery to remove the prostate. The American Urological Association estimates that more than 150,000 men annually in the U.S. have surgery to address BPH.

"One of the most common complications of prostate surgery is erectile dysfunction, caused by inadvertent damage to the cavernous nerve during surgery. There is currently no effective therapy for preventing these complications," said Andrew R. Blight, Ph.D., Acorda Therapeutics' Chief Scientific Officer. "The data from this study are consistent with previous preclinical work, indicating that GGF2 can improve erectile function after cavernous nerve damage, either through neuroprotection or stimulation of nerve regeneration. Based on the existing data, we believe that GGF2 may have the potential to also address other peripheral nerve injuries."

The platform presentation, "GGF2 Is Neuroprotective In A Rat Model Of Cavernous Nerve Injury-Induced Erectile Dysfunction," given by Arthur Burnett, M.D., included data from a study conducted by the Departments of Urology and Neurology at the Johns Hopkins University School of Medicine. It is the second collaborative effort between Acorda and independent academic institutions exploring the use of GGF2 to improve erectile function. Results from a previous preclinical study, conducted by Ottawa Hospital Research Institute at the University of Ottawa and presented by principal investigator Anthony Bella, M.D. at the American Urology Association 2011 annual meeting, also showed GGF2 improved erectile function following CN injury. The current study extended previous observations over a wider dose range and used electron microscopy to assess the injured nerves.

The study evaluated erectile function in five treatment groups of rats: two groups that did not have CN injury, one of which received an inactive control solution and the other received 15 mg/kg of GGF2, and three groups with a crush injury of the CN that received the inactive control, the 15 mg/kg dose of GGF2 or a lower dose of GGF2 (5 mg/kg). Treatments were administered subcutaneously 24 hours before the injury, 24 hours after and then once weekly for five weeks.

Nerve function was assessed using electrical stimulation of the nerve and recording intracavernous pressure, a standard measure of erectile function. During low-level stimulation, pressure was increased more in the lower dose GGF2 group than in the higher dose group or the inactive control group. During higher-level stimulation, pressure was improved in both lower and higher dose GGF2 groups compared to the control group, and was similar to the two groups that did not receive nerve injury. Electron microscopic evaluation of the cavernous nerve showed a greater number of nerve fibers in the GGF2 treated groups at 5 weeks following the injury.

GGF2 is Acorda's leading development candidate from the Company's neuregulin program. Neuregulins are a class of naturally occurring protein growth factors that have multiple effects on the nervous and cardiovascular systems. Acorda has ongoing studies of GGF2 in a number of cardiac and neurological indications, including heart failure, peripheral nerve injury and stroke. Results from Acorda's Phase 1 clinical study in heart failure are expected by the end of 2012.