16,000,000 Shares ARIAD Pharmaceuticals, Inc. Common Stock ($0.001 par value per Share) UNDERWRITING AGREEMENTUnderwriting Agreement • October 27th, 2010 • Ariad Pharmaceuticals Inc • Biological products, (no disgnostic substances) • New York
ARIAD Pharmaceuticals, Inc., a Delaware corporation (the “Company”), proposes, subject to the terms and conditions contained herein, to sell to you, Jefferies & Company, Inc. (“Jefferies”) and Oppenheimer & Co. Inc. (“OpCo”), acting as Representatives (the “Representatives”) of the underwriters named on Schedule I to this Agreement (the “Underwriters”), an aggregate of 16,000,000 shares (the “Firm Shares”) of the Company’s common stock, $0.001 par value per share (the “Common Stock”). In addition, the Company proposes to grant to the Underwriters an option to purchase up to an additional 2,400,000 shares (the “Option Shares”) of Common Stock from the Company for the purpose of covering over allotments in connection with the sale of the Firm Shares. Upon execution and delivery by the Representatives and the Company by 8:30 A.M. New York time on October 26, 2010 of a supplemental pricing agreement in the form attached hereto as Exhibit A, the aggregate number of Firm Shares to be purchas
