The first patient has been dosed in MAP US2, an open-label extension clinical trial evaluating RHB-104 as a treatment for Crohn’s disease, according to its maker, RedHill Biopharma.
MAP US is an ongoing, randomized, double blind, multicenter Phase 3 clinical trial (NCT01951326) comparing the effectiveness and safety of fixed-dose combination RHB-104 and a placebo. MAP US2 is an extension of that trial.
Those conducting the MAP US trial plan to enroll about 410 patients with moderate to severe Crohn’s disease — those with Crohn’s Disease Activity Index (CDAI) scores between 220 and 450.
The trial has enrolled 266 patients so far, with completion of enrollment expected before the end of 2017. The work is being done at about 150 clinical sites in the United States, Canada, Australia and several other countries.
MAP US is also evaluating RHD-1o4’s pharmacokinetics, or movement through the body. Data generated from the study is intended to support a U.S. New Drug Application (NDA) request for RHB-104.
The MAP US2 open-label extension trial (NCT03009396) will assess the effectiveness and safety of fixed-dose combination RHB-104 in about 100 Crohn’s patients who have completed the 26 weeks of treatment in the MAP US trial.
The 100 have an active level of the disease, indicated by CDAI scores above 150. Patients taking part in the extension study will be offered RHB-104 treatment for an additional 52 weeks. The primary endpoint, or measurement of the treatment’s effectiveness, will be disease remission after 16 weeks of treatment, reflected in a CDAI score of less than 150.
RedHill said in a press release that it plans more open-label clinical trials of RHB-104. They will be aimed at obtaining additional clinical data for marketing efforts.
A second independent Data and Safety Monitoring Board (DSMB) meeting for the MAP US trial is planned by mid-year. The agenda will include an interim effectiveness analysis, and a discussion of whether to stop the trial early if results look promising.
Late last year the board recommended that the study continue, RedHill said.
RHB-104 is composed of three antibiotics: rifabutin, clarithromycin, and clofazamine. The drug has potent intracellular, anti-mycobacterial and anti-inflammatory properties, RedHill said.
It was developed in response to evidence that the bacterial subspecies Mycobacterium avium paratuberculosis (MAP) can cause Crohn’s in patients predisposed to the disease.