PHILADELPHIA, Sept. 12, 2013 (GLOBE NEWSWIRE) -- Hemispherx Biopharma (NYSE MKT:HEB) announced that at the 53rd annual meeting of Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) in Denver, Colorado during September 9-13, 2013, that William Mitchell, MD, Ph.D., Professor Pathology, Microbiology, and Immunology, Vanderbilt University, presented the results of a study of Hemispherx product, Alferon N Injection ®, the only multi-species, natural interferon approved in the U.S. for the treatment of human refractory HPV genital warts, against wild type and oseltamivir (Tamiflu)-resistant H7N9 influenza virus. The increasing prevalence of oseltamivir-resistant Influenza A Virus, particularly against H7N9, has been widely reported and is due in large part to the fact that just a single-step mutation in this genetically unstable virus makes it resistant to oseltamivir. Dr. Mitchell, who is member of the Board of Directors of Hemispherx, discussed new experiments on the inhibition of Tamiflu ®-resistant H7N9 virus by Alferon N Injection ®. These experiments were conducted at Kansas State University by Professor Juergen Richt, DVM, Ph.D., Director of the U.S. Department of Homeland Security Center of Excellence for Emerging and Zoonotic Animal Diseases (CEEZAD), Regents Distinguished Professor of Veterinary Medicine at Kansas State University and an Eminent Scholar of Kansas Bioscience Association (KBA) along with his staff. Dr. Mitchell described the results with Alferon ®, including in-vitro experiments directed against inhibiting the Tamiflu ®-resistant H7N9 highly pathogenic influenza strain. Tamiflu ® (oseltamivir) and Alferon ® were tested in A549 cells for antiviral activity in vitro against the wild-type (wt) human A(H7N9) isolate A/Anhui/1/2013 (wt Anhui 1) and a patient isolate (A/Shanghai/1/2013 (NA-292K; Shanghai 1-NA292K)) with resistance to oseltamivir. The wt Anhui 1 was sensitive to both Tamiflu ® and Alferon ®. The Shanghai 1-NA292K virus was resistant to Tamiflu ® treatment but was sensitive to Alferon ® when tested in A549 cells. These initial results showed that:
- Tamiflu ® and Alferon ® have a significant inhibitory effect on the wild-type A(H7N9) virus. Alferon ® but not Tamiflu ® had a significant inhibitory effect on oseltamivir-resistant neuraminidase mutant Shanghai 1-NA292K.
- Alferon ® is similar to oseltamivir in reduction of titers from wt A(H7N9) isolates following 48 hours exposure to each drug
- Alferon ® appears to be highly effective as an inhibitor the A(H7N9) strain which demonstrates marked resistance to oseltamivir (Tamiflu ®)
- Tamiflu ®-resistant H7N9 viruses are associated with poor clinical outcomes. The potential for pandemic spread is dependent on the acquisition of additional mutations in the viral hemagglutinin gene allowing efficient human to human spread. Alferon offers an evidence based new therapeutic strategy to mitigate the health hazards associated with the potential pandemic spread of neuraminidase inhibitor-resistant human influenza viruses.