RedHill Biopharma Ltd. (NASDAQ: RDHL) announced that its experimental drug RHB-204 demonstrated comparable efficacy to RHB-104 in killing Mycobacterium avium subspecies paratuberculosis (MAP) in laboratory testing. The results were achieved using lower doses of two active ingredients compared to RHB-104, according to the company's statement.

RHB-204 is designed as an optimized formulation of RHB-104 for treating Crohn's disease. The drug contains clarithromycin, rifabutin and clofazimine in a fixed-dose oral capsule. RedHill reported that the comparable results were achieved in both spot and phage assays across several MAP strains.

"The demonstration of RHB-204's comparability to RHB-104 is an important step forward in the ongoing development of RHB-204 for MAP-related CD, following the pathway to approval guided by the FDA at our positive meeting," said Reza Fathi, PhD, Senior VP, R&D at RedHill.

The company's previous Phase 3 study of RHB-104 met its primary endpoint, showing 36.7% of patients achieved clinical remission at week 26 compared to 22.4% in the placebo group. RedHill plans to conduct a Phase 2 study of RHB-204 specifically in MAP-positive Crohn's disease patients.

RHB-204 has received FDA Fast Track and Orphan Drug Designation for non-tuberculous mycobacteria disease. The drug is patent protected through 2041 and has potential for up to 12 years of U.S. market exclusivity under the GAIN Act.

The company is pursuing partnerships and non-dilutive funding sources for the RHB-204 program, including through grant applications and ongoing discussions with external funding sources.