RedHill Announces Opaganib Chinese Patent Against Ebola Valid Until 2035

RedHill Biopharma Ltd., a specialty biopharmaceutical company, recently announced the issuance of a Notice of Allowance for a new Chinese patent covering opaganib, a therapy aimed at inhibiting the replication of single-stranded RNA viruses, including the Ebola Disease Virus. This patent, valid through 2035, bolsters the company's intellectual property portfolio and marks the first China patent in the Ebola patent family. This milestone highlights the potential of opaganib, which has demonstrated significant antiviral activity and survival benefits in studies.

Opaganib, an orally administered small molecule, is in development for various conditions such as COVID-19, acute respiratory distress syndrome, and several oncology indications. Additionally, it is part of two U.S. government-sponsored countermeasures programs for Acute Radiation Syndrome and Sulfur Mustard exposure. The drug's safety and efficacy have been well-documented, making it suitable for addressing nuclear and chemical exposures as well as viral pandemics. Its resistance to viral mutations and ease of administration and distribution make it particularly valuable.

In U.S. Army studies, opaganib emerged as the first host-directed molecule to show in vivo activity against the Ebola virus, resulting in a significant increase in survival rates. Moreover, it demonstrated strong synergistic effects in vitro when combined with remdesivir, enhancing viral inhibition while preserving cell viability.

Ebola virus disease (EVD), as defined by the Centers for Disease Control and Prevention (CDC), is a severe and often fatal illness caused by ebolaviruses, primarily found in sub-Saharan Africa. Transmission usually occurs through contact with infected animals or humans. The disease progresses from initial "dry" symptoms like fever and fatigue to "wet" symptoms such as diarrhea and unexplained bleeding. Currently, there are only two FDA-approved therapies for EVD caused by the Zaire ebolavirus: Inmazeb and Ebanga, both of which are monoclonal antibody treatments administered intravenously. There is an urgent need for small molecule therapies that are effective against multiple ebolavirus strains, less likely to be affected by viral mutations, and easier to store and distribute.

Opaganib (ABC294640) is a first-in-class, orally administered sphingosine kinase-2 (SPHK2) selective inhibitor with anticancer, anti-inflammatory, and antiviral properties. It targets several potential diseases, including gastrointestinal acute radiation syndrome (GI-ARS), COVID-19, and cholangiocarcinoma. The drug's mechanism involves inhibiting multiple pathways, inducing autophagy and apoptosis, and disrupting viral replication by inhibiting three sphingolipid-metabolizing enzymes in human cells (SPHK2, DES1, and GCS).

Selected by the U.S. government's Radiation and Nuclear Countermeasures Program (RNCP), opaganib is under development as a potential treatment for Acute Radiation Syndrome (ARS). The drug has shown antiviral activity against SARS-CoV-2 and other viruses like Influenza A and Ebola. In a study by the United States Army Medical Research Institute of Infectious Diseases (USAMRIID), opaganib increased survival time significantly in an in vivo Ebola virus study. It also displayed synergy with remdesivir in enhancing viral inhibition in vitro.

Opaganib is expected to remain effective against emerging viral variants due to its host-targeted approach. Clinical data from Phase 2/3 studies in COVID-19 patients showed improved viral RNA clearance and faster recovery times. The drug has demonstrated safety and tolerability in over 470 individuals through multiple studies. Additionally, opaganib has received Orphan Drug designation from the FDA for treating cholangiocarcinoma and has shown promise in renal fibrosis and other oncology, radioprotection, viral, inflammatory, and gastrointestinal indications.

RedHill Biopharma Ltd. focuses on gastrointestinal and infectious diseases. They promote Talicia for treating Helicobacter pylori infection and Aemcolo for travelers' diarrhea. Their late-stage development programs include opaganib, RHB-107 for non-hospitalized COVID-19, RHB-102 for chemotherapy-induced nausea, RHB-104 for Crohn's disease, and RHB-204 for pulmonary nontuberculous mycobacteria disease.