On Sept. 8, 2020, RedHill Biopharma announced that opaganib demonstrated potent inhibition of SARS-CoV-2, the virus that causes COVID-19, achieving complete blockage of viral replication in an in vitro model of human lung bronchial tissue. Opaganib is a first-in-class, orally-administered, sphingosine kinase-2 (SK2) selective inhibitor with dual anti-inflammatory and anti-viral activity that targets a host cell component, unaffected by viral mutation, thus minimizing the likelihood of resistance. Opaganib was being evaluated in global Phase 2/3 and U.S. Phase 2 clinical studies for the treatment of severe COVID-19 pneumonia.

Working in collaboration with the University of Louisville Center for Predictive Medicine, opaganib was studied in a 3D tissue model of human bronchial epithelial cells (EpiAirway^™) which morphologically and functionally resembles the human airway and is similar to the model used to discover SARS-CoV-2². This study was designed to evaluate the in vitro efficacy of opaganib in inhibiting SARS-CoV-2 infection and included a positive control of remdesivir, a drug with known antiviral activity.

Results from this study showed a clear and compelling antiviral effect of opaganib against SARS-CoV-2. Opaganib demonstrated the most potent activity compared to all compounds tested, including the positive control, remdesivir. Treatment of cells infected with SARS-CoV-2 resulted in a dose-dependent inhibition of virus production without compromising cell membrane integrity, a measure of cell viability and drug safety, further demonstrating opaganib’s promising potential for treating patients with COVID-19.

Opaganib at 1mg/ml (a pharmacologically relevant concentration) completely inhibited viral replication as measured after three days of incubation. This potent opaganib activity compares favorably with remdesivir data as the active control in the RedHill study which is consistent with published remdesivir data.  Data from the study is planned to be submitted to a peer-reviewed journal.

The ongoing global multi-center, randomized, double-blind, parallel-arm, placebo-controlled Phase 2/3 study evaluating opaganib for the treatment of patients with severe COVID-19 pneumonia continues to enroll with a target of up to 270 patients requiring hospitalization and treatment with supplemental oxygen. The study recently received approval in Israel and has been approved in the United Kingdom, Italy, Russia and Mexico, with further expansion progressing.