HSRx antiviral drug tests effective against Zika virus

HSRx Biopharmaceutical, a leading developer of polyfunctional-powered combination drugs for infectious and age-related chronic disease conditions, confirmed its orally administered broad-spectrum antiviral drug candidate, HSRx 431, is effective against the Zika virus.

HSRx expects to begin human trials early in 2017 and will seek accelerated drug approval from the US Food & Drug Administration.

Screening studies conducted by SRI International in their Shenandoah Valley facilities confirmed the effectiveness of HSRx 431 against the Zika virus. Previously conducted in vivo studies demonstrated the drug candidate’s safety and effectiveness against dengue and chikungunya infections. Additional studies on HSRx 431 for Zika will be conducted in parallel by SRI International. Concurrently, the development of clinical protocols and FDA registration will be completed for Zika human safety trials.

Zika virus disease, for which the World Health Organization reports there is no vaccine or drug treatment, is transmitted primarily by Aedes aegypti mosquitoes, which are present in the Americas, Africa, the Caribbean, Asia and the Pacific.

Florida, with hundreds of Zika cases, and Puerto Rico, with 5,000, are especially vulnerable. The US Centers for Disease Control (CDC) advises that the Aedes mosquito is present in some 30 states, and Anthony Fauci, MD, director of the U.S. National Institute of Allergy and Infectious Diseases (NIAID), notes that 25% of Puerto Rico’s population of 3.55 million can be expected to contract Zika over the next year.

Dr Fauci and NIAID Senior Scientific Advisor David Morens, MD suggest, “With respect to treatment, the arbovirus pandemics suggest that the one-bug-one-drug approach is inadequate; broad-spectrum antiviral drugs effective against whole classes of viruses are urgently needed.”

HSRx Director of Biology Joshua Costin, PhD, a virologist, said HSRx 431 is designed to meet that need, which, he notes, “is timely for an additional reason: Any Zika vaccine approval could be complicated and delayed if new research findings on the Zika/dengue virus connection prove accurate.”

Antibodies generated by infection usually provide immunity against subsequent infection, but antibody dependent enhancement (ADE), first reported as a theory by Scott Halstead, MD, a leading authority on viruses spread by mosquitoes, allows the dengue virus to deliver follow-on infections in which antibodies actually magnify the severity of illness. Recently completed research shows human serum containing dengue antibodies enhances Zika infection 200-fold.

The CDC advises that more than a third of the world’s population lives in areas at risk for dengue, and 400 million additional people are infected annually. Dengue is endemic in Puerto Rico, Latin America, Southeast Asia, the Pacific Islands, the Caribbean Islands, and like Zika, is expected soon to cause widespread infection in the US.