Vedanta Biosciences Receives Fast Track Designation for VE303 and Presents Phase 2 Data at Digestive Disease Week

VE303 receives Fast Track designation for prevention of recurrent C. difficile infection ahead of global pivotal Phase 3 study

Exploratory analyses from the VE303 Phase 2 CONSORTIUM study identify statistically significant relationships between VE303 bacterial species and multiple parameters that provide further mechanistic support for VE303’s observed efficacy 

CAMBRIDGE, MA, May 8, 2023 Vedanta Biosciences, a clinical-stage company that is developing a potential new category of oral therapies based on defined bacterial consortia, today announced that the U.S. Food and Drug Administration (FDA) granted Fast Track designation to Vedanta’s defined bacterial consortium candidate, VE303, for the prevention of recurrent Clostridioides difficile infection (rCDI). Fast Track designation is a process designed to facilitate the development and expedite the review of drugs that treat serious conditions and fill an unmet medical need. Vedanta also announced the details of a podium presentation of research informed by the VE303 Phase 2 CONSORTIUM study at Digestive Disease Week (DDW) 2023, held in Chicago, Illinois, May 6-9.

The presented analyses review multiple aspects of the pharmacodynamic response to VE303 in patients at high risk for rCDI, including how safety and efficacy correlate with dosing regimen, consortium strain colonization, metabolic changes, and restoration of a patient’s gut microbial community. The strong correlation between the presence of VE303 strains and both beneficial metabolic changes and nonrecurrence of CDI provides mechanistic support for the study’s observed efficacy results.

A disrupted intestinal microbiome from recent antibiotic exposure can lead to overgrowth of C. difficile. In the United States, approximately 500,000 people develop CDI each year, with symptoms that can include diarrhea, fever, abdominal pain, and cramping. Antibiotics are used to treat CDI and are generally successful, but they can further perturb the microbiome. As a result, an estimated 20% or more of these patients go on to have recurrent CDI episodes, which can leave them increasingly debilitated. Building on the positive Phase 2 data that were recently published in JAMA, the analyses presented at DDW provide additional evidence that VE303 strains colonize robustly and work to more quickly restore a disrupted microbiome to a normal, healthy state.

“The FDA’s decision to grant Fast Track designation to VE303 underscores the continuing need for medical innovation for this condition. Over 150,000 people experience recurrent CDI annually in the U.S. alone, and this requires scalable, effective treatment solutions,” said Jeffrey L. Silber, M.D., Chief Medical Officer of Vedanta Biosciences. “Fecal microbiota transplants and other donor-derived treatments are often prescribed—they can be effective, but they can vary greatly in composition and potency, and they may carry a risk of transmitting infectious agents. Vedanta’s approach of growing the strains for our defined bacterial consortia from pure clonal cell banks is a highly scalable process that obviates the need for fecal donors and leads to a consistently manufactured candidate. We look forward to initiating our global Phase 3 pivotal study for VE303, RestoratiVE303, later in 2023.”

About the VE303 DDW Presentation

Title: Pharmacodynamic response to a defined bacterial consortium, VE303, in patients with Clostridioides difficile infection (CDI): Results of the Phase 2 CONSORTIUM study

Presenter: Rajita Menon, Ph.D.

Overview: The research reviews various aspects of the Phase 2 CONSORTIUM study of VE303. The study was a randomized, double-blind, placebo-controlled, dose-finding trial in individuals at high risk of rCDI. After completing a course of antibiotics for a laboratory-confirmed qualifying CDI episode, subjects were randomized in a 1:1:1 ratio to receive low-dose VE303, high-dose VE303, or placebo orally once daily for 14 days. In the Phase 2 study, the VE303 high dose arm had an acceptable safety profile and compared with placebo, reduced the odds of developing rCDI through Week 8 by over 80%. The VE303 high dose also led to superior VE303 strain colonization at 14 days, achieving long-term engraftment, and promoted early restoration of the microbiota and beneficial metabolites.

To aid in the understanding of the mechanisms underlying the observed clinical efficacy, fecal samples were collected and analyzed at multiple timepoints. Among the 378 microbial species identified in these samples, the only ones significantly associated with non-recurrence were three of the strains in VE303. Several of the VE303 strains were associated with beneficial metabolic changes within the first 14 days. These observations suggest that VE303 may protect against rCDI via multiple mechanisms—both directly, through growth and preferential establishment of the VE303 strains in the gut relative to more pathogenic species; and indirectly, through synthesis of beneficial metabolites and enhanced recovery of the broader gut microbiome.

This research presentation was developed by Vedanta in collaboration with researchers at the University of Massachusetts Medical School and Mt. Sinai School of Medicine.

About VE303

VE303 is a defined bacterial consortium therapeutic candidate designed for the prevention of recurrent Clostridioides difficile infection (rCDI). It consists of eight strains that were rationally selected using Vedanta’s discovery engine. VE303 is produced from pure, clonal bacterial cell banks, which yield a standardized drug product in powdered form and bypass the need to rely on direct sourcing of donor fecal material of inconsistent composition. Vedanta reported positive topline results in October 2021 from the Phase 2 CONSORTIUM trial, in which VE303 was associated with a 31.7% absolute risk reduction in the rate of recurrence when compared with placebo, representing a greater than 80% reduction in the odds of a CDI recurrence. Vedanta believes VE303 has the potential to become a first-in-class therapeutic based on a defined bacterial consortium. Vedanta Biosciences received a $5.4 million research grant from the Combating Antibiotic Resistant Bacteria Biopharmaceutical Accelerator (CARB-X) in 2017. Additionally, the positive results of the Phase 2 study, first reported in October 2021, triggered a $23.8 million contract option from the Biomedical Advanced Research and Development Authority (BARDA) to support a Phase 3 clinical study of VE303. This project has been funded in part with federal funds from the Department of Health and Human Services; Administration for Strategic Preparedness and Response; BARDA, under contract number 75A5012C00177 for a contract value up to $81.9 million. VE303 was granted Orphan Drug Designation in 2017 and Fast Track Designation in 2023 by the U.S. Food and Drug Administration (FDA) for the prevention of recurrent CDI.

About Vedanta Biosciences

Vedanta Biosciences is leading the development of a potential new category of oral therapies based on defined consortia of bacteria isolated from the human microbiome and grown from pure clonal cell banks. The company’s clinical-stage pipeline includes product candidates being evaluated for the prevention of recurrent C. difficile infection, inflammatory bowel diseases, food allergy, and liver disease. These investigational therapies are grounded in our team’s pioneering research – published in leading journals including ScienceNature, Cell, and JAMA – to identify beneficial bacteria that live symbiotically within the healthy human gut, fight pathogens, and induce a range of potent immune responses. Vedanta Biosciences controls a foundational portfolio of more than 70 patents and has built what it believes is the industry-leading platform for development of defined bacterial consortia drugs. This platform includes one of the largest libraries of bacteria derived from the human microbiome, vast datasets from human interventional studies, proprietary capabilities in consortium design, and end-to-end capabilities for CGMP-compliant manufacturing of oral drug candidates spanning cell banking, fermentation, lyophilization, and fill finish. 

About Digestive Disease Week®

Digestive Disease Week® (DDW) is the largest international gathering of physicians, researchers and academics in the fields of gastroenterology, hepatology, endoscopy and gastrointestinal surgery. Jointly sponsored by the American Association for the Study of Liver Diseases (AASLD), the American Gastroenterological Association (AGA) Institute, the American Society for Gastrointestinal Endoscopy (ASGE) and the Society for Surgery of the Alimentary Tract (SSAT), DDW is an in-person and virtual meeting from May 6-9, 2023. The meeting showcases more than 3,100 abstracts and hundreds of lectures on the latest advances in GI research, medicine and technology. More information can be found at  



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