Hemispherx Biopharma exploring possible research programs in Zika virus

The recent orphan drug designations of Ampligen® for Ebola and Alferon® N for MERS viruses by the European Regulatory authorities demonstrates the global need for drugs that possess broad antiviral activities against emerging viruses.

Taxonomy of Flavivirus
Zika virus is a member of the flavivirus family. Like West Nile Virus, both viruses are transmitted by bites of the Aedes aegyptic mosquito. The Zika virus is suspected of causing an increase in babies born in Brazil with abnormally small heads, a serious birth defect known as microcephaly. At present, there are no known vaccines for Zika. The World Health Organization (WHO) estimates there could be 3 million to 4 million cases of Zika in the Americas this year. Recently, cases of Zika infection have also been reported secondary to sexual contact and blood transfusions.

Possible Zika Studies: Hemispherx scientists are exploring the hypothesis that intranasal (IN) use of Ampligen® or oral use of Alferon® in non-pregnant patients with active Zika viral infection could decrease viral load in blood and other body fluids, such as saliva and semen could shorten the time period during which the virus may be transmitted, and/or could decrease viral related tissue pathology. In addition, the symptomatic period may be shortened. This would be similar to the successful approach previously used for Tamiflu in treating early influenza infections.

Ampligen® Tests
In rodent studies, Ampligen®, an experimental therapeutic, has shown activity against the Modoc flavivirus induced encephalitis when administered pre- or post-infection, with positive effects on both morbidity (paralysis) and mortality being observed (Antimicrobial Agents and Chemotherapy, 47:777-782, 2003). In another flavivirus model with West Nile virus in different rodent populations intraperitoneally administered Ampligen® increased survival at least 2 fold (Antiviral Chemistry and Chemotherapy, 15:67-75, 2004). A clinical protocol similar to an ongoing seasonal influenza vaccine protection clinical program at the University of Alabama (Vaccine, 32:5490-5495, 2104), is envisioned in which at risk populations would receive Ampligen® delivered intranasally. Other earlier studies have also suggested that such intranasal (IN) administrative routes can be associated with a systemic antiviral and other biological effects of Ampligen®.

Alpha Interferon Tests
Alpha interferons have also shown activity against specific flaviviruses in rodent models. For example, recombinant alpha interferon reduced morbidity (paralysis) and mortality when given either pre+post or post-infection with Modoc virus (Antimicrobial Agents and Chemotherapy, 47:777-782, 2003). Natural alpha interferon (e.g. Alferon® N) could show similar or greater activity if previous findings of 6-80 fold greater activity over recombinant alpha interferons against a variety of different viruses, including MERS, are borne out in studies of flavivirus.

Alpha interferons, including Alferon® N, have previously shown protection against tissue damage in a low dose oral formulation in non-human primates (Antiviral Research, 110:175-180, 2014) against the highly pathogenic avian influenza virus (H5N1). Alferon® LDO (low dose oral) is also generally well-tolerated in human volunteers.

Previous FDA Authorizations for Clinical Trials in Flavivirus and Influenza

Previously, the Company participated in an FDA authorized clinical trial in the flavivirus class against West Nile Virus (WNV) with Principal Investigators at the Weill Medical College of Cornell University. The protocol was entitled "Double-Blind, Placebo-Controlled Trial of Alpha-Interferon (Alferon) Therapy for West Nile Meningoencephalitis". Many public health officials believe that the new cases of Zika virus are likely to surge in coming months in the Americas. To facilitate ease of treatment in potential new outbreaks of Zika infections, the Company is considering an oral delivery route of Alferon® N, e.g., Alferon® LDO. Alferon® LDO was previously authorized by the FDA for a prevention and treatment study protocol in influenza.

At present, the Company is in active dialogue with governmental representatives within the United States. The Company’s objective is to offer both products to governmental laboratories for further testing.