Benzinga | Mar 2, 2021 07:13AM EST

Seres Therapeutics Announces Achievement of Target Enrollment in SER-287 Phase 2b ECO-RESET Study for Ulcerative Colitis

Seres Therapeutics, Inc. (NASDAQ:MCRB) announced today that the Company has achieved target enrollment of the Phase 2b ECO-RESET clinical study of SER-287 in patients with mild-to-moderate ulcerative colitis (UC) in both the U.S. and Canada. SER-287, Seres' second microbiome therapeutic to reach late-stage clinical trials following a successful Phase 3 readout for SER-109, could represent a new therapeutic paradigm for UC by targeting underlying biological drivers of the disease. The results of this study will inform Seres' broader development efforts in ulcerative colitis and other programs that target modulation of host inflammation and immunity.

"People with ulcerative colitis and other inflammatory bowel diseases are in need of safe and effective treatment options, especially for mild-to-moderate forms of the disease. ECO-RESET achieved its target enrollment even amid the ongoing COVID-19 pandemic, a reflection of this high unmet need," said Lisa von Moltke, M.D., Chief Medical Officer of Seres. "We believe microbiome therapeutics offer the potential for an alternative treatment approach for inflammatory bowel diseases and have been committed to advancing microbiome therapeutics to address this need. We're pleased that SER-287, our most advanced UC program, has now reached this trial enrollment milestone."

The Phase 2b ECO-RESET study (Clinicaltrials.gov identifier: NCT03759041) is a multicenter, randomized, placebo-controlled study which has enrolled the targeted 201 patients with active mild-to-moderate UC. Two groups of patients are receiving different doses of SER-287, both following pre-conditioning with a short course of oral vancomycin. A third group is receiving placebo. The study's primary endpoint will evaluate clinical remission measured after 10 weeks of SER-287 administration. Endoscopic improvement will be measured as a secondary efficacy measure.

Based upon feedback obtained from the U.S. Food and Drug Administration (FDA) on the SER-287 Phase 2b study design, Seres believes the study could serve as one of two required pivotal trials supporting a Biologics License Application (BLA). The Company expects to share topline clinical data from ECO-RESET in mid-2021.

Mild-to-moderate UC is the most common form of the disease, representing a majority of the patient population in the U.S. First-line therapies for UC are only modestly effective. Non-responders have limited treatment options because potent immunosuppressive therapies have serious side effects which may be hard to justify in patients with mild-to-moderate disease. An unmet need exists for an effective, safer alternative therapeutic approach for mild-to-moderate UC patients that is not immunosuppressive.

"Seres is grateful to the patients, principal investigators and clinical research teams who have made this study possible. Their commitment to the trial's successful execution despite the challenges of COVID-19 has been remarkable," said Eric Shaff, President and Chief Executive Officer of Seres. "The data generated from this important study will inform our ongoing clinical efforts for SER-287 and SER-301 in UC as well as other indications through our reverse translational approach, supporting Seres' efforts to continue driving forward microbiome therapeutics that can transform the standard of care for patients."