RHB-107 (INN: upamostat) (formerly MESUPRON) is a proprietary, first-in-class orally-administered S1 serine protease inhibitor targeting cancer, inflammatory lung diseases and gastrointestinal diseases. It is also being evaluated as a treatment for COVID-19. A U.S. Phase 2/3 study with RHB-107 in an outpatient setting is planned to be initiated in early 2021.

RHB-107 represents a new, non-cytotoxic approach to cancer therapy with several potential mechanisms of action to inhibit tumor invasion and metastasis.

RHB-107 has undergone several Phase 1 studies and two Phase 2 studies, in locally advanced non-metastatic pancreatic cancer and in metastatic breast cancer, demonstrating its clinical safety and tolerability profile in over 300 patients. The Phase 2 studies with RHB-107 in both indications suggested activity as measured by both tumor response rate and overall survival of patients when administered in combination with first-line chemotherapeutic agents.

RHB-107 is also planned to be evaluated in combination with opaganib (Yeliva®) in an ongoing Phase 2a study in cholangiocarcinoma.

RHB-107 was granted FDA Orphan Drug designation for the adjuvant treatment of pancreatic cancer.

RedHill is also evaluating utilization of RHB-107 in several inflammatory gastrointestinal indications.

COVID-19 Development Program

RHB-107’s combined antiviral and potential tissue-protective action also make it a strong candidate for evaluation as a treatment for COVID-19 infection.

A recent study evaluated the antiviral activity of RHB-107 in an in vitro model of human lung bronchial tissue, showing potent inhibition of SARS-CoV-2 viral replication. RHB-107 demonstrated excellent antiviral activity, with viral replication being strongly inhibited in a dose-depended manner at pharmacologically relevant concentrations. A U.S. Phase 2/3 study with RHB-107 in an outpatient setting is planned to be initiated in Q4/2020.

RedHill acquired the worldwide exclusive development and commercialization rights to RHB-107 (excluding China, Hong Kong, Taiwan and Macao) for all indications from Munich-based WILEX AG in June 2014.