Summit Therapeutics plc 
(‘Summit’ or the ’Company’)

Summit to Highlight Potential of Precision Antibiotic Ridinilazole to Treat C. difficile Infection and Reduce Recurrent Disease at ID Week 2018

Oxford, UK, and Cambridge, MA, US, 26 September 2018 – Summit Therapeutics plc (NASDAQ: SMMT, AIM: SUMM), a leader in new mechanism antibiotic innovation, announces that it will present data on its Phase 3-ready precision antibiotic ridinilazole for the treatment of C. difficile infection at ID Week, 3-7 October 2018 in San Francisco, CA.

Details of the presentations are below.

Oral Presentation

Title: Ridinilazole (RDZ) for Clostridium difficile infection (CDI): Correlation of In Vitro Spectrum of Activity with Human Gut Microbiome Profiles from a Phase 2 Clinical Trial
Session: Oral Abstract Session: Translating Microbiome Science into Practice
Date: 6 October 2018, 11:15AM PDT
Location: W 2002
Authors: Richard Vickers, Ellie J C Goldstein, Diane Citron, David Snydman, Cheleste M. Thorpe and Anne V. Kane

Poster Presentations

Title: Combined Analysis of the In Vitro Activity of Ridinilazole (RDZ) Against More Than 500 Clostridium difficile (CD) Clinical Isolates and Impact of RDZ on Cell Morphology
Session: Poster Abstract Session: Novel Agents
Date: 5 October 2018
Location: S Poster Hall
Authors: Esther Duperchy, Eugénie Bassères, Kevin Garey, and Richard Vickers

Title: Pharmacokinetics and Safety of Ridinilazole (RDZ), a Potential New Therapy for Clostridium difficile Infection (CDI): from Animal Models to Patients
Session: Poster Abstract Session: Novel Agents
Date: 5 October 2018
Location: S Poster Hall
Authors: Esther Duperchy, Sumita Chowdhury, Richard Vickers, and Neil Robinson

Title: Ridinilazole (RDZ) for Clostridium difficile Infection (CDI): Impact of Diagnostic Method on Outcomes from a Phase 2 Clinical Trial
Session: Poster Abstract Session: Novel Agents
Date: 5 October 2018
Location: S Poster Hall
Authors: Richard Vickers, Sumita Chowdhury, and Mark Wilcox

Title: Selecting Clostridium difficile Infection (CDI) Outcome Measures Relevant to Public Health Concerns: Experience From a Ridinilazole (RDZ) Phase 2 Trial
Session: Poster Abstract Session: Treatment of AMR Infections
Date: 6 October 2018
Location: S Poster Hall
Authors: Richard Vickers and Sumita Chowdhury

Copies of the presentations will be made available on the Company’s website,, at the start of each session.

About Summit Therapeutics
Summit Therapeutics is a leader in antibiotic innovation. Our new mechanism antibiotics are designed to become the new standards of care for the benefit of patients, and create value for payors and healthcare providers. We are currently developing new mechanism antibiotics for C. difficile infection and gonorrhoea and are using our proprietary Discuva Platform to expand our pipeline. For more information, visit and follow us on Twitter @summitplc.


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