辉瑞美股招股说明书(2025-11-20版)

Pfizer Inc. $500,000,000 FLOATING RATE NOTES DUE 2027$1,000,000,000 3.875% NOTES DUE 2027$1,000,000,000 4.200% NOTES DUE 2030$1,250,000,000 4.500% NOTES DUE 2032 The underwriters expect to deliver the notes through the facilities of The Depository Trust Company (“DTC”) for the accounts of its direct participants, includingClearstream Banking,société anonymeand Euroclear Bank S.A./N.V., as operator of the Euroclear System, against payment therefor in New York, New York on or aboutNovember21, 2025. Table of Contents TABLE OF CONTENTS CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTSSUMMARY PROSPECTUS ABOUT THIS PROSPECTUSCAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTSINFORMATION ABOUT PFIZER INC.INFORMATION ABOUT PFIZER INVESTMENT ENTERPRISES PTE. LTD.INFORMATION ABOUT PFIZER NETHERLANDS INTERNATIONAL FINANCE B.V.RISK FACTORSUSE OF PROCEEDSDESCRIPTION OF DEBT SECURITIES OF PFIZER INC. DESCRIPTION OF DEBT SECURITIES OF PFIZER INVESTMENT ENTERPRISES PTE. LTD. DESCRIPTION OF DEBT SECURITIES OF PFIZER NETHERLANDS INTERNATIONAL FINANCE B.V. ENFORCEMENT OF CIVIL LIABILITIES AND SERVICE OF PROCESS No person is authorized to give any information or to make any representations other than those contained or incorporated by reference in thisprospectus supplement or the accompanying prospectus and any free writing prospectus we may provide you in connection with this offering.We and the underwriters take no responsibility for, and can provide no assurance as to the reliability of, any other information that others maygive you. This prospectus supplement and the accompanying prospectus are not an offer to sell or the solicitation of an offer to buy anysecurities in any jurisdiction where it is unlawful. Neither the delivery of this prospectus supplement or the accompanying prospectus, nor anysale of notes made under these documents, will, under any circumstances, create any implication that there has been no change in our affairssince the date of this prospectus supplement, the accompanying prospectus or any free writing prospectus we may provide you in connection Table of Contents prospectus, is accurate only as of the date of the documents containing the information, unless the information specifically indicates thatanother date applies. Our business, financial condition, results of operations and prospects may have changed since those dates. This document is in two parts. The first is this prospectus supplement, which describes the specific terms of this offering. The second part, theaccompanying prospectus, contains a description of our debt securities and gives more general information, some of which may not apply to thisoffering. This prospectus supplement also adds to, updates and changes information contained in the accompanying prospectus. If the description of theoffering varies between this prospectus supplement and the accompanying prospectus, you should rely on the information in this prospectus supplement. References in this prospectus supplement to “Pfizer,” the “Company,” “we,” “us” and “our” are to Pfizer Inc. and its consolidated subsidiaries unlessotherwise stated or the context so requires. Solely for convenience, the trademarks referred to in this prospectus supplement are without the “®” and “™” symbols, but such references are notintended to indicate, in any way, that the applicable owner will not assert, to the fullest extent under applicable law, its rights or the rights of the Table of Contents CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS This prospectus supplement and the accompanying prospectus, as well as the information incorporated by reference in this prospectus supplement andthe accompanying prospectus, may include forward-looking statements made within the meaning of Section27A of the Securities Act of 1933, asamended (the “Securities Act”), and Section21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Such forward-lookingstatements involve substantial risks, uncertainties and potentially inaccurate assumptions. These statements may be identified by using words such as“will,” “may,” “could,” “likely,” “ongoing,” “anticipate,” “estimate,” “expect,” “project,” “intend,” “plan,” “believe,” “assume,” “target,” “forecast,”“guidance,” “goal,” “objective,” “aim,” “seek,” “potential,” “hope” and other words and terms of similar meaning or by using future dates. We includeforward-looking information in our discussion of the following, among other topics: our anticipated operating and financial performance, includingfinancial guidance and projections; reorganizations, business plans, strategy, goals and prospects; expectations for our product pipeline (includingproducts from completed or anticipated acquisitions),in-lineproducts and product candidates, including anticipated regulatory submissions, data read-outs, study starts, approvals, launches, discontinuations, clinical trial results and other developing data; revenue c