PUMA BIOTECHNOLOGY, INC. (a Delaware corporation) 7,500,000 Shares of Common Stock UNDERWRITING AGREEMENTUnderwriting Agreement • October 24th, 2012 • Puma Biotechnology, Inc. • Pharmaceutical preparations • New York
Puma Biotechnology, Inc., a Delaware corporation (the “Company”), confirms its agreement with Merrill Lynch, Pierce, Fenner & Smith Incorporated (“Merrill Lynch”), Leerink Swann LLC (“Leerink”) and each of the other Underwriters named in Schedule A hereto (collectively, the “Underwriters,” which term shall also include any underwriter substituted as hereinafter provided in Section 10 hereof), for whom Merrill Lynch and Leerink are acting as representatives (in such capacity, the “Representatives”), with respect to (i) the sale by the Company and the purchase by the Underwriters, acting severally and not jointly, of the respective numbers of shares of Common Stock, par value $0.0001 per share, of the Company (“Common Stock”) set forth in Schedule A hereto and (ii) the grant by the Company to the Underwriters, acting severally and not jointly, of the option described in Section 2(b) hereof to purchase all or any part of 1,125,000 additional shares of Common Stock. The aforesaid 7,500,000
