On May 8, 2020, RedHill Biopharma announced the U.S. Food and Drug Administration (FDA) had approved its Investigational New Drug application for a Phase 2a clinical study evaluating its investigational drug, opaganib (Yeliva, ABC294640)1, in patients with confirmed moderate-to-severe SARS-CoV-2 infection.

A total of 139 subjects have been dosed with opaganib to date in ongoing and completed Phase 1 and Phase 2 clinical studies in oncology indications, in pharmacokinetic studies in healthy volunteers in the U.S., under the existing FDA-approved expanded access requests from physicians for individual oncology patients and under expanded access for COVID-19 patients in Israel, establishing safety and tolerability in humans both in the U.S. and ex-U.S.

The randomized, double-blind, placebo-controlled Phase 2a study aims to enroll up to 40 patients with moderate-to-severe SARS-CoV-2 infection and pneumonia requiring hospitalization and supplemental oxygenation. The Company expects to promptly initiate patient enrollment. Patients will be randomized at a 1:1 ratio to receive either opaganib or placebo on-top of standard-of-care. The primary objective of the study is to evaluate the reduction in total oxygen requirement over the course of treatment for up to 14 days. Secondary endpoints include time to 50% reduction in oxygen requirements, the proportion of patients without fever at Day 14, and proportion with negative nasal swabs at Day 14. This clinical trial is not powered for statistical significance.

Preliminary findings from six moderate-to-severe COVID-19 patients treated with opaganib in Israel under compassionate use have shown that all the patients demonstrated both subjective and objective significant measurable clinical improvement within days following treatment initiation with opaganib, including decreased required supplemental oxygenation, higher lymphocyte counts and decreased C-reactive protein (CRP) levels. All six patients analyzed were weaned from oxygen and discharged from the hospital. Opaganib has been well tolerated and showed clinical improvement both with and without hydroxychloroquine. At the time of treatment initiation, all of the patients were hospitalized, suffered from moderate-to-severe acute respiratory symptoms related to SARS-CoV-2 infection, were hypoxic, and required supplemental oxygen while being treated with standard-of-care, mostly hydroxychloroquine.

Pre-clinical data have demonstrated both anti-inflammatory and anti-viral activities of opaganib, with the potential to reduce lung inflammatory disorders, such as pneumonia, and mitigate pulmonary fibrotic damage. Several prior pre-clinical studies support the potential role of sphingosine kinase-2 (SK2) in the replication-transcription complex of positive-strand single-stranded RNA viruses, similar to coronavirus, and its inhibition may potentially inhibit viral replication. Pre-clinical in vivo studies have demonstrated that opaganib decreased fatality rates from influenza-virus infection and ameliorated Pseudomonas aeruginosa-induced lung injury by reducing the levels of IL-6 and TNF-alpha in bronchoalveolar lavage fluids.