EXHIBIT 10.39

Amendment No. 4 to the

Pfizer Inc. Executive Severance Plan

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(New material underlined; deletions crossed out)

Section 2.1(c) of Appendix A of the Pfizer Inc. Executive Severance Plan is amended to read as follows:

(c)    His or her Official Notification Date is on or after December 21, 2018 and on or before April 21, 2023October 21, 2022 or his Date of Termination is on or before June 30, 2023December 19, 2022. “Official Notification Date” means the date an eligible employee’s Notice Period begins.