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| Important Notices: About the Tender Offer and Additional Information and Where to Find It This communication is for internal informational purposes only and is neither a recommendation, an offer to purchase nor a solicitation of an offer to sell securities. On December 14, 2018, GlaxoSmithKline plc (“GSK”), GlaxoSmithKline LLC and Adriatic Acquisition Corporation (“AAC”) filed with the U.S. Securities and Exchange Commission (the “SEC”) a tender offer statement on Schedule TO regarding the tender offer by AAC to purchase all of the issued and outstanding shares of common stock (the “Shares”) of TESARO, Inc. (the “Company”). The Company filed a solicitation/recommendation statement with the SEC on Schedule 14D-9 with respect to the tender offer on December 14, 2018. Holders of Shares are urged to read the tender offer statement and the Schedule 14-9 (as each may be updated and amended from time to time) as they contain important information that holders of Shares should consider before making any decision regarding tendering their Shares. These materials will be made available to TESARO’s stockholders at no expense to them by Innisfree M&A Incorporated, the Information Agent, for the tender offer. In addition, the tender offer statement and other documents filed by GSK and TESARO with the SEC are available for free at the SEC’s website at www.sec.gov. This communication is not intended for distribution to, or use by, any person or entity in any jurisdiction or country where such distribution or use would be contrary to local law or regulation. This communication does not constitute, nor does it form part of, any offer or invitation to buy, sell, exchange or otherwise dispose of, or any issuance, or any solicitation of any offer to sell or issue, exchange or otherwise dispose of any securities. This communication does not constitute investment, legal, tax, accountancy or other advice or a recommendation with respect to such securities, nor does it constitute the solicitation of any vote or approval in any jurisdiction. The depositary for the tender offer is Computershare Trust Company, N.A. For questions relating to the tender offer, please call the Information Agent, Innisfree M&A Incorporated toll-free at (888) 750-5834. |