A preclinical study testing the generic drug nafamostat in human cells shows it can help block SARS-CoV-2 infection.

Biopharmaceutical company Covistat, an Ensysce Biosciences subsidiary, is repurposing nafamostat — an intravenous drug anticoagulant to treat pancreatitis and other diseases — into oral and inhaled COVID-19 therapies. Nafamostat works as a lock-and-key mechanism, shutting out the coronavirus by deactivating the TMPRSS2 enzyme that enables SARS-CoV-2's spike proteins to gain entry — locking its doorway into our cells.

"This data supports nafamostat's formidable defense against the coronavirus, whether used alone or in combination with antiviral therapies that have shown promise against COVID-19," Dr. Lynn Kirkpatrick, Ensysce CEO, said. "We look forward to further studying nafamostat's ability to stop this disease's progression and help preclude people from becoming infected by SARS-CoV-2 and other seasonal coronaviruses."

The new study was completed in July by independent research laboratory, Epithelix. Nafamostat's potent protease activity blocked SARS-CoV-2 from infecting cells in a lung cell model generated from 14 pooled donors. The model demonstrated nafamostat's safety across a wide range of concentrations with no toxicity, loss of cellular integrity or inflammatory reactions, such as cytokine storm. Using the Epithelix MucilAir platform, the preclinical results showed nafamostat increased cilia beating — the movement of hair-like structures on the surface of cells that help sweep lungs clean of mucus and foreign objects.

Covistat has previously shown that nafamostat can be safely administered orally to healthy individuals, and the drug is being studied by scientists as a potential antiviral therapy.