The antiviral product, HDT-201, will utilize company’s RNA/LION™ platform technology and ultimately will be available to the public.

SEATTLE, WA (August 8, 2022) – HDT Bio Corp., a developer of immunotherapies for infectious diseases and oncology, announced today it has been awarded a nearly $1.8 M grant from the U.S. Army Medical Research Acquisition Activity to develop HDT-201, which uses RNA and the company’s proprietary LION™ delivery system, into an antiviral intranasal spray that can stimulate the body’s innate immune system to treat and prevent a broad spectrum of deadly human viruses.

“Over the past 20 years, we have witnessed numerous deadly outbreaks of Ebola, Zika, SARS, MERS, and now SARS-CoV-2,” said Steve Reed, HDT Bio CEO. “The spread of viral diseases, whether due to unintentional outbreaks or bioterrorism, poses a significant risk to military health and readiness. By developing HDT-201 into an intranasal spray device, it could become part of a soldier’s kit, allowing for rapid response to deadly viral pathogens. We are grateful for the Army’s support and look forward to providing a product that can protect those who protect us.”

HDT-201 uses a RIG-I activating RNA (RAR) molecule, an innate immune agonist derived and  modified from the Hepatitis C virus RNA genome. RAR was developed by Dr. Michael Gale, Jr., Professor of University of Washington, Seattle, a Scientific Founder of HDT Bio. “My team is especially excited to see our technology moving forward to clinical development,” Dr.Gale added.

The RAR is delivered by HDT Bio’s proprietary LION™ system into cells where it binds to RIG-I protein, which recognizes viral RNA and activates the body’s innate immune response to stimulate antiviral genes that suppress infection. RIG-I signaling also enhances the production of antibodies against a virus.

 HDT Bio’s research has shown that its RAR molecule is a broad spectrum antiviral that can trigger responses to a variety of deadly respiratory and other viral pathogens. The company is developing HDT-201 as a therapeutic and a preventative. It already has developed animal data demonstrating the RAR molecule prevents replication of influenza A virus and SARS-CoV-2, with cell culture data showing that it suppresses and controls the replication of other respiratory viruses, such as common cold coronaviruses, respiratory syncytial virus, and mosquito-transmitted viruses including West Nile virus, dengue virus, and Japanese encephalitis virus.

 During the development process, HDT Bio will perform safety and potency studies of the antiviral nasal spray required by the U.S. Food and Drug Administration (FDA) in preparation for potential clinical trials, which could begin in 2025. Ultimately the product can be used by the civilian population.

The U.S. Army Medical Research Acquisition Activity, 820 Chandler Street, Fort Detrick MD 21702- 5014 is the awarding and administering acquisition office. This work was supported by the Assistant Secretary of Defense for Health Affairs, through the Department of Defense, in the amount of $1,793,172 under Award No. W81XWH2210755. Opinions, interpretations, conclusions, and recommendations are those of the author and are not necessarily endorsed by the Assistant Secretary of Defense for Health Affairs or the Department of Defense. In conducting research using animals, the investigators adhere to the laws of the United States and regulations of the Department of Agriculture.


HDT Bio is a Seattle-based, clinical-stage biopharmaceutical development company.  With core technology and expertise in nucleic acid formulation, the company develops products that seek to harness host-directed immune responses.  HDT Bio’s work focuses on infectious disease and oncology vaccines and therapeutics through early-stage collaborations with partners worldwide. The company’s vaccine platform, repRNA/LION™, combines formulation and adjuvant ingredients to stabilize and deliver self-amplifying RNA to the immune system to stimulate responses. HDT Bio’s COVID19 vaccine is the first self-amplifying RNA vaccine to ever receive a regulatory authorization.