Summit Therapeutics Announces Exercise of Underwriters’ Over-Allotment Option

OXFORD, United Kingdom, Sept. 15, 2017 -- Summit Therapeutics plc (NASDAQ:SMMT) (AIM:SUMM), the drug discovery and development company advancing therapies for Duchenne muscular dystrophy and C. difficile infection, today announces that the underwriters of its underwritten public offering have exercised in full their over-allotment option to purchase an additional 218,850 American Depositary Shares (“ADSs”) at the public offering price of $12.00 per ADS, less underwriting discounts and commissions.  After the over-allotment exercise, the total number of ADSs to be sold by Summit in this public offering will increase to 1,677,850. The ADSs trade on the NASDAQ Global Market. Each ADS represents five ordinary shares of Summit.

Canaccord Genuity Inc. and JMP Securities LLC are acting as joint lead book-running managers for the offering. Needham & Company, LLC is acting as lead manager and H.C. Wainwright & Co., LLC is acting as co-manager.

The securities are being issued and sold pursuant to an effective shelf registration statement (including a base prospectus) that was previously filed with the Securities and Exchange Commission (the “SEC”). The final prospectus supplement relating to the offering was filed with the SEC on September 14, 2017 and is available on the SEC’s website at www.sec.gov. Copies of the final prospectus supplement and the accompanying prospectus relating to the offering may be obtained by contacting Canaccord Genuity Inc., Attention: Syndicate Department, 99 High Street, 12th Floor, Boston, Massachusetts 02110, telephone: +1 (617) 371-3900 or JMP Securities LLC, Prospectus Department, 600 Montgomery Street, 10th Floor, San Francisco, California 94111, telephone: +1 (415) 835- 8985.  This press release is being issued pursuant to and in accordance with Rule 135e under the United States Securities Act of 1933, as amended (the “Securities Act”).

This press release does not constitute a prospectus and does not constitute or form part of any offer or invitation to sell or issue, or the solicitation of an offer to purchase or acquire, any of the ordinary shares or ADSs or any other securities in the United States of America or in any other jurisdiction. Securities may not be offered or sold in the United States of America absent registration or an exemption from registration under the Securities Act. Any public offering of securities to be made in the United States will be made by means of a prospectus. Such prospectus will contain or incorporate by reference detailed information about the issuer and its management and financial statements. In particular, and without limitation, no offer of securities to the public (as that term is understood in the EU Prospectus Directive) is being made in the United Kingdom or in any other country in the European Economic Area which has implemented the EU Prospectus Directive.

About Summit Therapeutics
Summit is a biopharmaceutical company focused on the discovery, development and commercialization 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.

For more information, please contact:

Summit           
Glyn Edwards / Richard Pye (UK office)             Tel: +44 (0)1235 443 951
Erik Ostrowski / Michelle Avery (US office)         +1 617 225 4455

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