Ansun BioPharma announced that the Division of Antiviral Products of the U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation to Ansun's first-in-class experimental compound DAS181, for the treatment of lower respiratory tract parainfluenza virus (PIV) infection in immunocompromised patients. PIV infection causes significant morbidity and mortality in immunocompromised patients as well as hospitalized patients, and currently there are no treatments available for patients infected with PIV.

"We have quietly been developing DAS181 to treat severely ill patients infected with PIV and other respiratory infectious diseases, including influenza, for a number of years, and the Breakthrough Therapy Designation granted by the FDA is a major milestone in the clinical development of this potentially lifesaving drug," said Dr. Nancy Chang, the CEO of Ansun BioPharma.

DAS181 utilizes a unique host-directed approach to block respiratory viruses by cleaving sialic acid receptors located in the human respiratory tract which are bound by most of the major respiratory viruses as they infect patients. DAS181 has demonstrated antiviral activity against three of the four major respiratory viruses, influenza virus (IFV), parainfluenza virus (PIV) and metapneumovirus (MPV), as well as human enterovirus-68 (EV-68). DAS181 blocks viral infection in a manner that makes it difficult for viruses that rely on sialic acid receptors for entry to develop resistance; and little to no resistance has been observed in multiple non-clinical and clinical studies.

The FDA grants Breakthrough Therapy Designation status to products that treat serious or life threatening conditions and that have preliminary clinical evidence that the drug may demonstrate substantial improvement over available therapies on one or more clinically significant endpoints.

Ansun recently completed a Phase 2 study of DAS181 for treatment of PIV infection in hospitalized, immunocompromised patients and is now in the planning stage of a Phase 3 study. In addition, Ansun has worked in collaboration with the FDA to make DAS181 available for treatment of over 130 pediatric and adult patients through compassionate use under single patient emergency IND applications.

In the U.S., approximately 55,000 to 200,000 hospitalized patients are diagnosed with PIV infection each year. Many of these hospitalizations are immunocompromised patients, including patients undergoing leukemia treatments, solid organ transplants and hematopoietic stem cell transplants. DAS181, if it successfully completes Phase 3 trials and is approved, could become the first product specifically available to meet this significant medical need.