PHILADELPHIA—Hemispherx Biopharma, Inc. presented a summary of the results of its Phase 1/2 study in a poster presentation entitled "Seasonal Influenza Vaccine and a TLR-3 Agonist, Rintatolimod (Ampligen®), Given Intranasally Produced Cross-Reactive IgA Antibodies Against Pathogenic H5N1 Influenza HA." The poster was given at the American Society for Microbiology (ASM) Biodefense Conference in Washington, DC on January 30, 2014.
On the news of the results presented in the poster, Hemispherx stock advanced 10.5 percent.
As the poster described, when FluMist®, a seasonal influenza vaccine, was administered intranasally in conjunction with Ampligen (an experimental therapeutic), 92 percent of the subjects elaborated specific immunoglobulin A (IgA) antibodies against at least one of the homologous seasonal vaccine strains. Healthy volunteers also showed, surprisingly, enhanced IgA levels against emerging avian influenza viruses with the potential for causing a pandemic in humans. These antibodies were against one or more of three different strains of H5N1, H7N9, and H7N3. Two-thirds of the recipients showed a greater than or equal to four-fold increase in specific IgA levels over baseline and some had measurable IgA levels one year after receiving FluMist in conjunction with Ampligen.
Dr. William Carter, Hemispherx CEO, notes that the molecule now called Ampligen, for which nasal passages have a large number of receptors, was discovered at Johns Hopkins. It has now been demonstrated to provide enhanced protection against a number of seasonal and pandemic viruses. “The next step,” he says, “is to survey for other pandemic viruses, for example, in the Pacific Rim, which is now experiencing new outbreaks>”
The published challenge study in adults (age 18 to 45) indicates that FluMist alone generates greater than or equal to four-fold increase in serum HAI antibody response (a level thought to be protective) in 24 percent of recipients despite the fact that 85 percent of recipients were estimated to have been protected (Treanor, et al. (2000) Vaccine, 18:899). In Europe FluMist is approved for individuals aged 2 to17 compared to ages 2 to 49 in the US.
Dr. Carter indicated that compared to systemic doses of Ampligen used in other clinical studies, the amount of intranasal Ampligen used in this study was as low as one eight thousandth (1/8,000) of the dose. In response to a question about safety, Dr. David Strayer, medical director at Hemispherx, indicated that there were no serious adverse events reported during the study and over 80 percent of the adverse events reported were mild.
The breadth of immune response suggests that other groups, particularly vulnerable to influenza and unprotected by FluMist alone, might benefit from an appropriate addition of an adjuvant.
In a related study, Dr. William M. Mitchell of Vanderbilt University presented a research paper on January 21, 2014 at the Keystone Symposia Conference on Pathogenesis of Respiratory Viruses entitled "Protection from Pulmonary Tissue Damage Associated with Infection of Cynomolgus Macaques by Highly Pathogenic Avian Influenza Virus (H5N1) by Low Dose Natural Human IFN-alpha Administered to the Buccal Mucosa." The presentation was the result of a collaborative project conducted at Viroclinics, Rotterdam, an internationally recognized research entity for the study of both seasonal and pandemic influenza viruses. The Vanderbilt-Viroclinics work is a parallel program aimed at developing protection when it is too late to administer a vaccine.
Using an established primate model for H5N1 infection, the collaborative team has evaluated the potential for the prophylactic mitigation of the pulmonary damage characteristic of fatal cases from primary influenza virus pneumonia using a low dose oral (LDO) formulation of a commercially available parenteral natural human interferon alpha (Alferon N Injection®). “We are very excited by this work as well, “ says Carter. The Viroclinics labs are internationally known and this work in non-human primates against a very virulent, very deadly virus, showed dramatic results.”
Hemispherx Biopharma, Inc. is an advanced specialty pharmaceutical company engaged in the manufacture and clinical development of new drug entities for treatment of seriously debilitating disorders. Hemispherx's flagship products include Alferon N Injection and the experimental therapeutics Ampligen and Alferon LDO. Ampligen is an experimental RNA nucleic acid being developed for globally important debilitating diseases and disorders of the immune system, including chronic fatigue syndrome. Because both Ampligen and Alferon LDO are experimental in nature, they are not designated safe and effective by a regulatory authority for general use and are legally available only through clinical trials. Hemispherx has patents comprising its core intellectual property estate and a fully commercialized product (Alferon N Injection) approved for sale in the U.S. and Argentina. The company wholly owns and exclusively operates a GMP-certified manufacturing facility in the United States for commercial products.