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

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.

Contacts

Summit Forward-looking Statements

Any statements in this press release about the Company’s future expectations, plans and prospects, including but not limited to, statements about the potential benefits of the CARB-X award, including whether the option segments will be exercised, the clinical and preclinical development of the Company’s product candidates, the therapeutic potential of the Company’s product candidates, the potential commercialisation of the Company’s product candidates, the sufficiency of the Company’s cash resources, the timing of initiation, completion and availability of data from clinical trials, the potential submission of applications for marketing approvals and other statements containing the words "anticipate," "believe," "continue," "could," "estimate," "expect," "intend," "may," "plan," "potential," "predict," "project," "should," "target," "would," and similar expressions, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including: the uncertainties inherent in the initiation of future clinical trials, availability and timing of data from ongoing and future clinical trials and the results of such trials, whether preliminary results from a clinical trial will be predictive of the final results of that trial or whether results of early clinical trials or preclinical studies will be indicative of the results of later clinical trials, expectations for regulatory approvals, laws and regulations affecting government contracts and funding awards, availability of funding sufficient for the Company’s foreseeable and unforeseeable operating expenses and capital expenditure requirements and other factors discussed in the "Risk Factors" section of filings that the Company makes with the Securities and Exchange Commission, including the Company’s Annual Report on Form 20-F for the fiscal year ended 31 January 2018. Accordingly, readers should not place undue reliance on forward-looking statements or information. In addition, any forward-looking statements included in this press release represent the Company’s views only as of the date of this release and should not be relied upon as representing the Company’s views as of any subsequent date. The Company specifically disclaims any obligation to update any forward-looking statements included in this press release.

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