Summit Therapeutics File US Annual Report on Form

Summit Therapeutics plc ("Summit", or the "Company")

SUMMIT THERAPEUTICS FILES US ANNUAL REPORT ON FORM 20-F

Oxford, UK, 31 March 2017 - Summit Therapeutics plc (AIM: SUMM, NASDAQ: SMMT), the drug discovery and development company advancing therapies for Duchenne muscular dystrophy and Clostridium difficile infection, provides notification that on 30 March 2017 the Company filed its US Annual Report on Form 20-F for the year ended 31 January 2017 with the US Securities and Exchange Commission ("SEC").

The Form 20-F is available to download, either from the Investors section of the Company website at www.summitplc.com or from the SEC website at www.sec.gov .

About Summit Therapeutics Summit is a biopharmaceutical company focused on the discovery, development and commercialisation of novel medicines for indications for which there are no existing or only inadequate therapies. Summit is conducting clinical programs focused on the genetic disease, Duchenne muscular dystrophy, and the infectious disease, Clostridium difficile infection. Further information is available at www.summitplc.com and Summit can be followed on Twitter (@summitplc).

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