RedHill Biopharma Ltd. announced the issue of a new Chinese patent Notice of Allowance covering opaganib as a therapyg for inhibition of single-stranded RNA virus replication (notably Ebola Disease Virus) from the Chinese National Intellectual Property Administration (CNIPA), valid through 2035 (Chinese Patent Application No.: 202110229970.9 issued April 29, 2024). This new patent adds to the existing intellectual property portfolio protecting opaganib across multiple indications and represents the first China patent in the Ebola patent family. U.S. Army studies suggest that opaganib may be the first host-directed molecule to show activity in vivo in Ebola virus disease, delivering a statistically significant increase in survival. Targeting multiple indications, including selection by two U.S. government countermeasures programs for Acute Radiation Syndrome and Sulfur Mustard exposure, oral opaganib, has a demonstrated safety and efficacy profile and is well-suited to viral pandemic scenarios, being viral mutation-resistant, and easy to administer and distribute. According to the Centers for Disease Control and Prevention (CDC), Ebola disease is a rare and often deadly illness, caused by infection by one of a group of four viruses, known as ebolaviruses, that are found primarily in sub-Saharan Africa and are known as: Zaire, Sudan, Taï Forest (formerly Côte d'Ivoire) and Bundibugyo.
Transmission of the disease is mostly through contact with an infected animal (bat or nonhuman primate) or a sick or dead person infected with an ebolavirus. The course of the illness typically progresses from "dry" symptoms initially (such as fever, aches and pains, and fatigue), and then progresses to "wet" symptoms (such as diarrhea, vomiting and unexplained hemorrhaging, bleeding or bruising) as the person becomes sicker. There are currently only two FDA-approved therapies to treat EVD caused by the Ebola virus, species Zaire ebolavirus, in adults and children; Inmazeb? (atoltivimab/maftivimab/odesivimab, Regeneron Pharmaceuticals, Inc), a combination
of three monoclonal antibodies and Ebanga? (ansuvimab-zykl, Ridgeback Biotherapeutics, LP), a single monoclonal antibody. Both are intravenously infused direct acting monoclonal antibody antivirals that bind to glycoproteins on the Ebola virus's surface to prevent the virus from entering a person's cells. There is an urgent need for host-directed small molecule therapies that may be effective against multiple strains of ebolavirus, less likely to be impacted by viral mutation, and that are easy to store, distribute and administer, especially in areas where healthcare services and infrastructures may be sub-optimal.  Opaganib, a proprietary investigational host-directed and potentially broad-acting drug, is a first-in-class, orally administered sphingosine kinase-2 (SPHK2) selective inhibitor with anticancer, anti-inflammatory and antiviral activity, targeting multiple potential diseases, including gastrointestinal acute radiation syndrome (GI-ARS), COVID-19, other viruses as part of pandemic preparedness, and cholangiocarcinoma (bile duct cancer). Opaganib's host-directed action is thought to work through the inhibition of multiple pathways, the induction of autophagy and apoptosis, and disruption of viral replication, through simultaneous inhibition of three sphingolipid-metabolizing enzymes in human cells (SPHK2, DES1 and GCS).