RHB-107 (INN: upamostat) (formerly MESUPRON) is a proprietary, first-in-class orally-administered potent inhibitor of serine proteases targeting multiple indications, including COVID-19, cancer, inflammatory lung diseases and gastrointestinal diseases. 

RHB-107 is being evaluated in a U.S. Phase 2/3 study for treatment of patients with symptomatic COVID-19 who do not require inpatient care (NCT04723527).

RHB-107’s combined antiviral and potential tissue-protective action make it a strong candidate for evaluation as a potential treatment for COVID-19 infection. RHB-107 targets human cell factors involved in preparing the spike protein for viral entry into target cells potentially minimizing the likelihood for resistance due to emerging viral variants with mutations in the spike protein.

RHB-107 has also demonstrated strong inhibition of SARS-CoV-2 viral replication in an in vitro human bronchial epithelial cell model and previous preclinical work demonstrated potential tissue-protective action. 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 approximately 200 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 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.