Summit Therapeutics Announces Pricing of U.S. Initial Public Offering and Nasdaq Global Market Listing

OXFORD, England--Summit Therapeutics plc, the drug discovery and development company advancing therapies for Duchenne muscular dystrophy and C. difficile infection, announces the pricing of its underwritten initial public offering of 3,450,000 American Depository Shares ("ADSs") at a public offering price of $9.90 per ADS, before underwriting discounts and commissions. The ADSs have been approved for listing on the NASDAQ Global Market and are expected to begin trading today under the ticker symbol "SMMT". Summit's ordinary shares will continue to trade on the AIM market of the London Stock Exchange following the offering.

In addition, Summit has granted the underwriters an option for a period of 30 days to purchase, at the public offering price less underwriting discounts and commissions, up to an additional 517,500 ADSs to cover any over-allotments. Each ADS represents five ordinary shares of Summit. Closing of the offering is expected to occur on or about March 10, 2015, subject to customary closing conditions.

JMP Securities and Oppenheimer & Co. are acting as joint book-running managers for the offering. Needham & Company is acting as lead manager.

A registration statement relating to these securities was declared effective by the United States Securities and Exchange Commission on March 4, 2015. This press release shall not constitute an offer to sell or a solicitation of an offer to buy any securities, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

The offering is being made only by means of a prospectus, copies of which may be obtained from JMP Securities LLC, Prospectus Department, 600 Montgomery Street, 10th Floor, San Francisco, CA 94111, telephone: +1 (415) 835-8985; from Oppenheimer & Co. Inc., Syndicate Prospectus Department, 85 Broad Street, 26th Floor, New York, NY 10004, telephone: +1 (212) 667-8563 and from Needham & Company, LLC, Prospectus Department, 445 Park Avenue, 4th floor, New York, NY 10022, telephone: +1 (800) 903-3268.

Notes to Editors

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.

Contacts

Summit
Glyn Edwards / Richard Pye, +44 (0)1235 443 951
(UK office)
or
Erik Ostrowski, +1-617-294-6607
(US office)