RedHill Biopharma’s experimental therapy RHB-104 significantly increases the remission and response rates of patients with Crohn’s disease, according to top-line Phase 3 trial results recently announced by the company.
The results, showing that the study met all primary and key secondary goals, were discussed in a conference call, which included a slide presentation.
RHB-104 is an oral antibiotic combination therapy with potent anti-bacterial and anti-inflammatory properties, targeting a bacterial infection of Mycobacterium avium paratuberculosis (MAP), suspected to cause Crohn’s disease.
The randomized, double-blind, placebo-controlled Phase 3 trial (NCT01951326), known as MAPUS, evaluated the safety and effectiveness of RHB-104 in people with moderate to severe Crohn’s disease, defined as Crohn’s Disease Activity Index (CDAI) between 220 and 450.
The study’s primary goal was remission (no signs of active disease), defined as a reduction in CDAI of less than 150 at week 26.
Secondary objectives included treatment response at week 26 (decrease in CDAI of at least 100 points), remission at week 16 and/or 52, and durable remission.
The study involved 331 participants (ages 18-75) enrolled at over 100 sites in the U.S., Canada, Europe, Israel, Australia, and New Zealand. Participants were randomized to receive five capsules a day of either RHB-104 (166 patients) or a placebo (165 patients), in addition to standard medication.
The study’s primary goal was met, with a statistically significant greater proportion of patients receiving RHB-104 achieving remission (37%), compared to those in the placebo group (23%).
Significantly more patients treated with RHB-104 also showed treatment response at week 26 and early remission at week 16 (44% and 42%, respectively), compared with those receiving placebo (31% and 29%, respectively).
Twice as many patients treated with RHB-104 patients had continuous remission throughout weeks 16 to 52 as those receiving placebo, which was statistically significant. However, the number of patients achieving remission at 52 weeks of treatment was not significantly different between the two groups.
RHB-104 was found to be generally safe and well tolerated, with similar low rates of serious adverse events between both groups, and low rates of discontinuation due to RHB-104-associated adverse events.
“Many patients with Crohn’s disease do not achieve remission on current standard-of-care therapies, which are accompanied with poor side effects,” David Graham, MD, the trial’s lead investigator, said in a press release.
“RHB-104 appears to have the potential to become a promising, new, orally-administered therapy for this important debilitating disease,” he added.
The company will continue to assess additional exploratory endpoints in the coming months, including the presence of MAP, quality of life, and how the body processes the therapy.
An extension study, MAPUS2 (NCT03009396), is ongoing to evaluate the therapeutic effects of RHB-104 in patients who still have active Crohn’s disease after 26 weeks of therapy in the MAPUS study.
According to Ira Kalfus, MD, RedHill’s medical director, the company plans to meet with the FDA to present the results of both studies and discuss a path toward potential approval for the therapy candidate.