PDUFA: Dec. 20 — Hemispherx Biopharma

Hemispherx Biopharma [NYSE: HEB] expects an FDA decision under the Prescription Drug User Fee Act (PDUFA) concerning the approval status of Ampligen (poly Izpoly C12U), being developed for the treatment of chronic fatigue syndrome (CFS).

Ampligen is a synthetic, specifically configured double-stranded RNA being developed for the treatment of globally important viral diseases and disorders of the immune system including chronic fatigue syndrome and AIDS. The Arthritis Advisory Committee (AAC) will meet December 20, 2012 to discuss the New Drug Application for CFS, which is currently under review by the FDA. The PDUFA review goal for the FDA to complete its review is February 2, 2013.

The mechanism of Ampligen (the compound rintatolimod) is thought to be a stimulation of the immune system through the binding to TLR-3, a receptor on the cell surface which detects pathogens immediately, before adaptive immunity can intervene against foreign invaders.

Hemispherx has on two occasions received warning letters from the FDA regarding its promotion of rintatolimod as safe and effective before approval from the FDA.

According to the company rintatolimod has been “generally well tolerated”, with a “low incidence of clinical toxicity”, principally when compared to the toxicity of the diseases it is used to treat. “No serious safety issues have resulted from the administration of ~75,000 doses IV (most commonly 400 mg) twice weekly for up to one year periods or greater. Animal toxicity studies support this observation in humans with primates indicating the greatest margin of safety.

Hemispherx Biopharma is a biopharmaceutical company engaged in the manufacturing and clinical development of new drug entities for treatment of viral and immune-based disorders. Hemispherx’s Alferon N Injection is fully commercialized for the intralesional treatment of refractory or recurring external condylomata acuminata in patients 18 years of age or older. Alferon Low Dose Oral is a new experimental drug delivery platform using the same highly purified, natural source alpha interferon as the injectable product.

It is estimated that up to 500,000 Americans have chronic fatigue syndrome.