Item 5.02 Departure of Directors or Principal Officers; Election of Directors; Appointment of Principal Officers

(c) Appointment of Principal Officer

On December 12, 2012, the Board of Directors of TESARO, Inc. (the "Company") appointed Edward C. English, age 45, as the Company's Vice President, Controller and Principal Accounting Officer. Mr. English will continue to report to Richard J. Rodgers, the Company's Executive Vice President, Chief Financial Officer, Secretary and Treasurer. Mr. English originally joined the Company in June 2012, as Controller. Prior to joining the Company, Mr. English served from 2011 to 2012 as Controller of Mascoma Corporation, a privately held renewable-fuel company, and prior to that served from 2007 to 2011 in a variety of positions of increasing responsibility at AMAG Pharmaceuticals, Inc., including as Corporate Controller, Vice President and Corporate Controller and finally Interim Chief Financial Officer. Before AMAG Pharmaceuticals, Mr. English spent 10 years at PRAECIS PHARMACEUTICALS Inc., where he held a variety of roles, including, immediately prior to its acquisition by GlaxoSmithKline PLC, the role of Vice President, Chief Financial Officer, Treasurer and Assistant Secretary. Mr. English started his career as a Certified Public Accountant with KPMG LLP in Boston, Massachusetts, where he held various positions, including audit manager within the Health Care and Life Sciences assurance practice. Mr. English holds an undergraduate degree from Georgetown University and a joint M.S. in accounting and M.B.A. from the Northeastern University Graduate School of Professional Accounting.

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