RHB-204 is an investigational, proprietary, fixed-dose, orally administered, antibiotic combination therapy containing clarithromycin, rifabutin, and clofazimine in development for the treatment of Crohn’s disease in Mycobacterium avium subspecies paratuberculosis-positive (MAP+) patients. RHB-204 also has potential for the treatment of pulmonary nontuberculous mycobacterial (NTM) disease caused by Mycobacterium avium complex (MAC).
RHB-204 for Crohn’s Disease:
RHB-204 is a next-generation formulation of RHB-104, in development for the treatment of Mycobacterium avium subspecies paratuberculosis-positive (MAP+) moderate to severe Crohn's disease. The development of RHB-204 builds on the positive results achieved in the randomized, double-blind, placebo-controlled 331-patient Phase 3 study of RHB-104 in active Crohn’s disease (the “MAP US” study), which successfully met its primary endpoint and secondary endpoints, as published in the Antibiotics journal.
RHB-204 contains the same antimicrobial agents as RHB-104 with potent intracellular, anti-mycobacterial, and anti-inflammatory properties, but with an optimized dosing profile designed to support enhanced tolerability, safety and adherence. RedHill announced that it received positive feedback from the FDA regarding the pathway to approval for RHB-204’s Crohn’s disease development program.
The development of RHB-204 and RHB-104 is based on the growing body of evidence supporting the hypothesis that Crohn’s disease is caused by MAP infection in susceptible patients.
RHB-204 for Pulmonary NTM Disease:
RHB-204 also has potential for the treatment of pulmonary nontuberculous mycobacterial (NTM) disease caused by Mycobacterium avium complex (MAC). A previously ongoing U.S. Phase 3 study of RHB-204, which aimed to evaluate its efficacy as a first-line treatment for pulmonary NTM disease in adults, was terminated in 2023 due to a low patient accrual rate.
RHB-204 has been granted FDA Fast Track designation and FDA Orphan Drug Designation for the treatment of NTM disease and QIDP Designation under the Generating Antibiotic Incentives Now Act (GAIN Act), extending U.S. market exclusivity for RHB-204 to a potential total of 12 years to be granted at the time of FDA approval. RHB-204 has additionally been granted EU Orphan Designation, providing eligibility for 10 years post-approval market exclusivity.
The terminated Phase 3 study evaluating RHB-204 for pulmonary NTM disease is registered on www.clinicaltrials.gov, a web-based service by the U.S. National Institute of Health, which provides public access to information on publicly and privately supported clinical studies.