Hemispherx announces publication of Ampligen Phase III data in Journal of Applied Research

Hemispherx Biopharma, Inc. (NYSE Amex:HEB) (the "Company"), announced the publication of a peer-reviewed article providing new data on Ampligen^® [rintatolimod; poly(I)·poly(C12,U)], an experimental therapeutic in Phase III clinical testing, in the current issue of The Journal of Applied Research. The report is entitled "Cardiac Toxicity in Chronic Fatigue Syndrome (CFS): Results from a Randomized 40-Week Multicenter Double-Blind Placebo Control Trial of Rintatolimod".  Findings include discussion of the sedentary lifestyle produced by extreme fatigue which is a significant risk factor for heart disease, a leading cause of death in patients with CFS. Thus, cardiac abnormalities, including abnormal electrocardiograms (EKGs), are common in CFS patients despite their relatively young age.

The AMP-516, Phase III FDA-authorized study in CFS evaluated the therapeutic effectiveness of Ampligen®, an experimental therapeutic, and included repeated measurements of the QT interval, a component of EKG testing.  Prolongation of the EKG QT interval is a known risk factor in sudden cardiac death (Long QT Syndrome) due to the induction of fatal cardiac arrhythmias. A greater portion of the placebo patients were found to have a significant prolongation of the QT interval compared to patients who had received Ampligen® twice weekly. The prolonged QT interval in the placebo group was associated with continued use of certain concomitant medications, which are known to prolong the QT interval and used by CFS patients in an attempt to mitigate symptoms of the disease.  In contrast, patients randomized to receive Ampligen were able to significantly reduce their dependency on these same medications.

Concomitant medications which increase the QT interval may carry a "black box" warning on their labels since prolonged QT intervals are associated with cardiac arrhythmias which may result in sudden death.

The AMP-516 study was one of the studies submitted to FDA in the Ampligen^® NDA, which resulted in the previously-announced November 25, 2009 Complete Response Letter, in which FDA requested that additional data be generated and submitted on effectiveness measures and potential QT interval effects.