Microbiome drug candidate prevents recurrence of C. difficile infection

RBX2660, a broad-spectrum microbiota suspension delivered to the intestinal tract, reached its primary endpoint of preventing recurrence of Clostridium difficile infection in the phase 2 PUNCH Open Label trial, according to a press release

The manufacturer, Rebiotix, said it now expects the drug candidate to enter phase 3 clinical development.

In the prospective, open label, controlled study, investigators compared prevention of recurrent CDI among 132 patients treated with RBX2660 and 110 historical controls treated with antibiotics at 31 active treatment sites and four control sites in the U.S. and Canada. Patients in the RBX2660 group received a dose at days 1 and 7.

Through 8 weeks, 78.8% of the RBX2660 group achieved treatment success compared with 51.8% of controls (P < .0001). The drug was generally well-tolerated, and the most common adverse events included diarrhea, abdominal pain, flatulence, constipation and distension.

These results confirm previous findings from the PUNCH CD2 study, which showed RBX2660 safely prevented recurrent CDI after a standard course of antibiotics.

The treatment success rate “demonstrates the potential of RBX2660 ... to rehabilitate the gut microbiome and break the cycle of C. diff recurrence,” Lee Jones, president and CEO of Rebiotix, said in the press release. “These results, coupled with the safety and efficacy data observed in our prior phase 2b and phase 2 clinical trials, position Rebiotix to advance RBX2660 into phase 3 clinical development, solidifying our standing as the most clinically advanced microbiome company in the industry.”

The FDA previously granted RBX2660 orphan drug status, fast track status and breakthrough therapy designation. – by Adam Leitenberger

Disclosures: Jones is employed by Rebiotix.