PFE Pfizer Inc

As filed with the Securities and Exchange Commission on February 23, 2024

Registration No. 333-     

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

PFIZER INC.

(Exact name of registrant as specified in its charter)

PFIZER INVESTMENT ENTERPRISES PTE. LTD.

(Exact name of registrant as specified in its charter)

c/o Pfizer Inc.

66 Hudson Boulevard East

New York, NY 10001-2192

(212) 733-2323

(Address, including zip code, and telephone number, including area code, of registrants’ principal executive offices)

Margaret M. Madden, Esq.

Senior Vice President and Corporate Secretary,

Chief Governance Counsel

Pfizer Inc.

66 Hudson Boulevard East

New York, NY 10001-2192

(212) 733-2323

(Name, address, including zip code and telephone number, including area code, of agent for service)

APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: From time to time after the effective date of this registration statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☒

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Pfizer Inc.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

PROSPECTUS

PFIZER INC.

DEBT SECURITIES

COMMON STOCK

PREFERRED STOCK

WARRANTS

DEPOSITARY SHARES

PURCHASE CONTRACTS

PURCHASE UNITS

GUARANTEES

PFIZER INVESTMENT ENTERPRISES PTE. LTD.

DEBT SECURITIES

Pfizer Inc. (“Parent”) may from time to time offer to sell debt securities, common stock, preferred stock, warrants, depositary shares, purchase contracts, purchase units or guarantees. Pfizer Investment Enterprises Pte. Ltd., a wholly-owned subsidiary of Parent (“Pfizer Singapore”), may from time to time offer to sell debt securities, which will be fully and unconditionally guaranteed by Parent. Each time we sell securities pursuant to this prospectus, we will provide a supplement to this prospectus that contains specific information about the offering and the specific terms of the securities offered. The prospectus supplement may also add to, update or change information contained in this prospectus. In addition, we may supplement, update or change any of the information contained in this prospectus by incorporating information by reference in this prospectus.

In addition, selling securityholders to be named in a prospectus supplement may offer our securities from time to time. To the extent that any selling securityholder resells any securities, the selling securityholder may be required to provide you with this prospectus and a prospectus supplement identifying and containing specific information about the selling securityholder and the terms of the securities being offered.

You should read this prospectus, the supplements to this prospectus and any incorporated documents carefully before you invest in any of our securities. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state or other jurisdiction where the offer or sale is not permitted.

We may offer and sell securities to or through one or more underwriters, dealers and agents, or directly to purchasers. The names and compensation of any underwriters or agents involved in the sale of securities will be described in a supplement to this prospectus.

The common stock of Parent is listed on the New York Stock Exchange (the “NYSE”) under the symbol “PFE.” If we decide to seek a listing of any securities offered by this prospectus, the applicable prospectus supplement will disclose the exchange or market on which such securities will be listed, if any, or where we have made an application for listing, if any.

Investing in our securities involves risk. You should carefully consider the risk factors incorporated in this prospectus by reference and described under the heading “Risk Factors” beginning on page 3.

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR DETERMINED IF THIS PROSPECTUS IS TRUTHFUL OR COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

The date of this prospectus is February 23, 2024.

TABLE OF CONTENTS

No person is authorized to give any information or to make any representations other than those contained or incorporated by reference in this prospectus, any accompanying prospectus supplement or any free writing prospectus we may provide you in connection with an offering. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus and any accompanying prospectus supplement are not an offer to sell or the solicitation of an offer to buy any securities in any jurisdiction where it is unlawful. Neither the delivery of this prospectus or any accompanying prospectus supplement, nor any sale of securities made under these documents, will, under any circumstances, create any implication that there has been no change in our affairs since the date of this prospectus, any accompanying prospectus supplement or any free writing prospectus we may provide you in connection with an offering or that the information contained or incorporated by reference is correct as of any time subsequent to the date of such information. You should assume that the information in this prospectus or any accompanying prospectus supplement, as well as the information incorporated by reference in this prospectus or any accompanying prospectus supplement, is accurate only as of the date of the documents containing the information, unless the information specifically indicates that another date applies. Our business, financial condition, results of operations and prospects may have changed since those dates.

ABOUT THIS PROSPECTUS

This prospectus is part of an “automatic shelf” registration statement that we filed with the Securities and Exchange Commission (the “SEC”), as a “well-known seasoned issuer” as defined in Rule 405 under the Securities Act of 1933, as amended (the “Securities Act”), using a “shelf” registration process. We may sell any combination of the securities described in this prospectus from time to time in one or more offerings, and selling securityholders may offer such securities owned by them from time to time. You should carefully read this prospectus and any accompanying prospectus supplement together with the additional information described under the heading “Where You Can Find More Information.”

This prospectus provides you with a general description of the securities that may be offered by Parent, Pfizer Singapore and/or selling securityholders. Each time we sell securities pursuant to this prospectus, we will provide a prospectus supplement that contains specific information about the terms of that offering, including the specific amounts, prices and terms of the securities offered. If this prospectus is inconsistent with the prospectus supplement, you should rely upon the prospectus supplement. In addition, the prospectus supplement may also add, update or change the information contained in this prospectus.

If you are in a jurisdiction where offers to sell, or solicitations of offers to purchase, the securities offered by this document are unlawful, or if you are a person to whom it is unlawful to direct these types of activities, then the offer presented in this document does not extend to you.

Wherever references are made in this prospectus to information that will be included in a prospectus supplement, to the extent permitted by applicable law, rules or regulations, we may instead include such information or add, update or change the information contained in this prospectus by means of a post-effective amendment to the registration statement of which this prospectus is a part, through filings we make with the SEC that are incorporated by reference in this prospectus or by any other method as may then be permitted under applicable law, rules or regulations. For purposes of this prospectus, any reference to a prospectus supplement may also refer to a free writing prospectus unless the context requires otherwise.

References in this prospectus to “Pfizer,” the “Company,” “we,” “us” and “our” are to Pfizer Inc. and its consolidated subsidiaries, including Pfizer Investment Enterprises Pte. Ltd., unless otherwise stated or the context so requires. References to “Parent” in this prospectus are to Pfizer Inc., excluding its consolidated subsidiaries. References in this prospectus to “Pfizer Singapore” refer to Pfizer Investment Enterprises Pte. Ltd.

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and any accompanying prospectus supplement, as well as the information incorporated by reference in this prospectus or any accompanying prospectus supplement, may include forward-looking statements made within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Such forward-looking statements involve substantial risks and uncertainties and potentially inaccurate assumptions.

We have tried, wherever possible, to identify such statements 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 include forward-looking information in our discussion of the following, among other topics:

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In particular, forward-looking information included or incorporated by reference in this prospectus may include statements relating to specific future actions, performance and effects, including, among others, the expected benefits of the organizational changes to our operations; our anticipated operating and financial performance; our ongoing efforts to respond to COVID-19, including our plans and expectations regarding Comirnaty and Paxlovid, and any potential future vaccines or treatments, including anticipated revenue and expectations for the commercial market for Comirnaty and Paxlovid; our expectations regarding the impact of COVID-19 on our business; expected patent terms; the expected impact of patent expiries and generic and biosimilar competition; the expected pricing pressures on our products and the anticipated impact to our business; the benefits expected from our business development transactions, including our December 2023 acquisition of Seagen Inc. (“Seagen”); our anticipated liquidity position; the anticipated costs, savings and potential benefits from certain of our initiatives, including our enterprise-wide Realigning our Cost Base program, which we launched in October 2023, and our Transforming to a More Focused Company program; our expectations regarding the impact from the 2023 tornado on our manufacturing facility in Rocky Mount, NC; our greenhouse gas emission reduction goals; our planned capital spending; and our capital allocation framework.

A list and description of risks, uncertainties and other matters can be found in Parent’s most recent Annual Report on Form 10-K and each of Parent’s subsequently filed Quarterly Reports on Form 10-Q, in each case, including in the sections thereof captioned “Forward-Looking Information and Factors That May Affect Future Results” and “Risk Factors,” in Parent’s Current Reports on Form 8-K, and in this prospectus and any accompanying prospectus supplement, in each case, including in the section thereof captioned “Risk Factors.” You should understand that it is not possible to predict or identify all such factors. Consequently, you should not consider any such list to be a complete set of all potential risks or uncertainties.

We cannot guarantee that any forward-looking statement will be realized. Achievement of anticipated results is subject to substantial risks, uncertainties and inaccurate assumptions. Should known or unknown risks or uncertainties materialize, or should underlying assumptions prove inaccurate, actual results could vary materially from past results and those anticipated, estimated or projected. You should bear this in mind as you consider forward-looking statements, and you are cautioned not to put undue reliance on forward-looking statements.

WE UNDERTAKE NO OBLIGATION TO PUBLICLY UPDATE FORWARD-LOOKING STATEMENTS, WHETHER AS A RESULT OF NEW INFORMATION, FUTURE EVENTS OR OTHERWISE, EXCEPT AS REQUIRED BY LAW OR BY THE RULES AND REGULATIONS OF THE SEC. YOU ARE ADVISED, HOWEVER, TO CONSULT ANY FURTHER DISCLOSURES WE MAKE ON RELATED SUBJECTS IN PARENT’S FORM 10-K, 10-Q AND 8-K REPORTS AND PARENT’S OTHER FILINGS WITH THE SEC.

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INFORMATION ABOUT PFIZER INC.

Pfizer Inc. is a research-based, global biopharmaceutical company. We apply science and our global resources to bring therapies to people that extend and significantly improve their lives through the discovery, development, manufacture, marketing, sale and distribution of biopharmaceutical products worldwide. We work across developed and emerging markets to advance wellness, prevention, treatments and cures that challenge the most feared diseases of our time. We collaborate with healthcare providers, governments and local communities to support and expand access to reliable, affordable healthcare around the world.

We are committed to strategically capitalizing on growth opportunities, primarily by advancing our own product pipeline and maximizing the value of our existing products, but also through various business development activities. We view our business development activity as an enabler of our strategies and seek to generate growth by pursuing opportunities and transactions that have the potential to strengthen our business and our capabilities. We assess our business, assets and scientific capabilities/portfolio as part of our regular, ongoing portfolio review process and also continue to consider business development activities that will help advance our business strategy.

Pfizer Inc. was incorporated under the laws of the State of Delaware on June 2, 1942. Our principal executive offices are located at 66 Hudson Boulevard East, New York, New York 10001-2192, and our telephone number is (212) 733-2323.

INFORMATION ABOUT PFIZER INVESTMENT ENTERPRISES PTE. LTD.

Pfizer Singapore is a recently formed, wholly-owned subsidiary of Parent. Pfizer Singapore is not an active trading company, is a “finance subsidiary” (as such term is used in Regulation S-X Rule 13-01) and has no assets or operations, and will have no assets or operations, other than as related to the issuance, administration and repayment of any debt securities that Pfizer Singapore has issued and may issue in the future that are fully and unconditionally guaranteed by Parent. No historical information relating to Pfizer Singapore is presented or incorporated by reference into this prospectus. The historical consolidated financial information of Pfizer as of December 31, 2023 and 2022, and for the fiscal years ended December 31, 2023, 2022 and 2021, is incorporated in this prospectus by reference to Parent’s Annual Report on Form 10-K for the fiscal year ended December 31, 2023. See “Where You Can Find More Information.”

Pfizer Singapore is a private company limited by shares incorporated under the laws of the Republic of Singapore on April 24, 2023 and was assigned company registration number 202315648E. The registered office of Pfizer Singapore is located at 10 Collyer Quay, #10-01 Ocean Financial Centre, Singapore 049315.

RISK FACTORS

You should consider carefully the information under the headings “Risk Factors” in Parent’s Annual Report on Form 10-K for the year ended December 31, 2023, in any applicable prospectus supplement and any risk factors set forth in Parent’s other filings with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, including Parent’s Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, before making an investment decision. If known or unknown risks or uncertainties materialize, our business operations, financial condition, operating results (including components of our financial results), cash flows, prospects, reputation or credit ratings could be adversely affected now and in the future, potentially in a material way. See “Where You Can Find More Information.”

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USE OF PROCEEDS

Unless the applicable prospectus supplement indicates otherwise, we intend to use net proceeds from the sale of the securities for general corporate purposes, including working capital, capital expenditures, payment of dividends, share repurchases, acquisitions and the refinancing of existing debt. We may use funds that are not immediately needed for these purposes to temporarily invest in short-term marketable securities. The use of any proceeds of debt securities issued by Pfizer Singapore will be subject to applicable Singapore law.

Unless set forth in an accompanying prospectus supplement, we will not receive any proceeds in the event that securities are sold by a selling securityholder.

DESCRIPTION OF DEBT SECURITIES OF PFIZER INC.

In this “Description of Debt Securities of Pfizer Inc.” section, references to the “Issuer” refer to Pfizer Inc. and its successors, as the issuer of debt securities that may be offered hereunder.

The Issuer may offer debt securities in one or more series, which may be senior debt securities or subordinated debt securities and which may be convertible into another security.

The following description briefly sets forth certain general terms and provisions of the debt securities. The particular terms of the debt securities offered by any prospectus supplement and the extent, if any, to which the following general terms and provisions may apply to the debt securities, will be described in an accompanying prospectus supplement. Unless otherwise specified in an accompanying prospectus supplement, the Issuer’s debt securities will be issued in one or more series under an indenture, dated as of September 7, 2018 (the “Parent indenture”), between the Issuer and The Bank of New York Mellon, as trustee. The Parent indenture is filed as an exhibit to the registration statement of which this prospectus forms a part, and any supplemental indenture will be filed as an exhibit to a document incorporated by reference herein, in connection with the issuance of any new series of debt securities offered and sold hereunder. In this “Description of Debt Securities of Pfizer Inc.” section, we refer to the Parent indenture, as amended and supplemented by each supplemental indenture applicable to a series of debt securities issued thereunder and offered hereby, as an “indenture.” We urge you to read the Parent indenture and relevant supplemental indenture because these documents, and not the summary below, will define your rights as a holder of debt securities. Capitalized terms used in the summary have the meanings specified in the indenture. The terms of the debt securities will include those set forth in the indenture and those made a part of the indenture by the Trust Indenture Act of 1939 (“TIA”). You should read the summary below, any accompanying prospectus supplement and the provisions of the indenture in their entirety before investing in the Issuer’s debt securities.

The aggregate principal amount of debt securities that may be issued under the indenture is unlimited. The prospectus supplement relating to any series of debt securities that the Issuer may offer will contain the specific terms of the debt securities. These terms may include, among others, the following:

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General

The Issuer may issue the debt securities in one or more series with the same or various maturities, at par or a premium or with original issue discount. Unless we inform you otherwise in a prospectus supplement, the Issuer may issue additional debt securities of a particular series without the consent of the holders of the debt securities of such series or any other series outstanding at the time of issuance. Any such additional debt securities, together with all other outstanding debt securities of that series, will constitute a single series of securities under the indenture.

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We will describe in an accompanying prospectus supplement any other special considerations for any debt securities that are denominated in a currency or currency unit other than U.S. dollars. In addition, debt securities may be issued where the amount of principal and/or interest payable is determined by reference to one or more currency exchange rates, commodity prices, equity indices or other factors. Holders of such securities may receive a principal amount or a payment of interest that is greater than or less than the amount of principal or interest otherwise payable on such dates, depending upon the value of the applicable currencies, commodities, equity indices or other factors. Information as to the methods for determining the amount of principal or interest, if any, payable on any date, and the currencies, commodities, equity indices or other factors to which the amount payable on such date is linked will be described in an accompanying prospectus supplement.

United States federal income tax consequences and special considerations, if any, applicable to any such series will be described in an accompanying prospectus supplement.

Unless otherwise specified in an accompanying prospectus supplement, the debt securities will be issued in fully registered form without coupons and in denominations of $2,000 and any integral multiple of $1,000 in excess thereof. Subject to the limitations provided in the indenture and in an accompanying prospectus supplement, debt securities that are issued in registered form may be transferred or exchanged at the designated corporate trust office of the trustee, without the payment of any service charge, other than any tax or other governmental charge payable in connection therewith.

Consolidation, Merger or Sale

The Issuer has agreed not to consolidate with or merge into any other person or convey or transfer its properties and assets as an entirety or substantially as an entirety to any other person, unless:

Upon any consolidation of the Issuer with, or merger of the Issuer into, any other person or any conveyance or transfer of the properties and assets of the Issuer as an entirety or substantially as an entirety in accordance with the foregoing requirements, the successor person will succeed to, and be substituted for, and may exercise every right and power of, the Issuer under the indenture with the same effect as if such successor person were an original party to the indenture, and thereafter the Issuer shall be relieved of all obligations and covenants under the indenture and the debt securities.

Modification of Indenture

Under the indenture, the Issuer and the applicable trustee may supplement the indenture for certain purposes which would not adversely affect the interests of the holders of debt securities of a series in any material respect without the consent of those holders. Under the indenture, the rights of the holders may be modified through a supplemental indenture if the holders of at least a majority in aggregate principal amount of the outstanding debt securities of all series affected by the modification (voting as one class) consent to it. No modification of the maturity date, principal or interest payment terms or premium payable on redemption, no modification of the currency for payment, no impairment of the right to sue for the enforcement of payment at the maturity of the debt security, no modification of any conversion rights, no modification reducing the percentage required for any such supplemental indenture or the percentage required for the waiver of compliance with certain provisions of the indenture or certain defaults, and no modification of the foregoing provisions or any other provisions relating to the waiver of past defaults or the waiver of certain covenants, is effective against any holder without its consent.

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Events of Default

Each of the following will constitute an event of default under the indenture with respect to debt securities of any series:

The supplemental indenture or the form of security for a particular series of debt securities may include additional events of default or changes to the events of default described above. The events of default applicable to a particular series of debt securities will be discussed in the prospectus supplement relating to such series. A default under our other indebtedness will not be a default under the indenture for the debt securities covered by this prospectus, and a default under one series of debt securities will not necessarily be a default under another series. The trustee may withhold notice to the holders of debt securities of any default (except for defaults that involve the Issuer’s failure to pay principal or interest) if it considers such withholding of notice to be in the best interests of the holders.

If an event of default with respect to outstanding debt securities of any series occurs and is continuing, then the trustee or the holders of at least 33% in principal amount of outstanding debt securities of that series may declare, in a written notice, the principal amount (or, if any of the securities of that series are original issue discount securities, such portion of the principal amount of such securities as specified in the terms thereof) plus accrued and unpaid interest on all debt securities of that series to be immediately due and payable. At any time after a declaration of acceleration with respect to debt securities of any series has been made and before a judgment or decree for the payment of money due has been obtained by the trustee, the event of default giving rise to such declaration of acceleration shall, without further act, be deemed to have been rescinded and annulled, if:

We refer you to the prospectus supplement relating to any series of debt securities that are discount securities for the particular provisions relating to acceleration of a portion of the principal amount of the discount securities upon the occurrence of an event of default.

If a default in the performance or breach of the indenture shall have occurred and be continuing, the holders of not less than a majority in principal amount of the outstanding securities of all series affected thereby, by notice to the trustee, may waive any past event of default or its consequences under the indenture. However, an event of default cannot be waived without the consent of the holders of each outstanding security of the series affected with respect to any series of securities in the following two circumstances:

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The trustee is not obligated to exercise any of its rights or powers under the indenture at the request, order or direction of any holders, unless the holders offer the trustee security or indemnity reasonably satisfactory to the trustee. Holders of a majority in principal amount outstanding of any series of debt securities may, subject to certain limitations, direct the time, method and place of conducting any proceeding or any remedy available to the trustee, or exercising any power conferred upon the trustee, for such applicable series of debt securities.

The Issuer is required to deliver an annual officer’s certificate to the trustee stating whether it is in default in the performance and observance of any of the terms, provisions and conditions of the indenture, and, if the Issuer is in default, specifying all such defaults and the nature and status thereof.

Payment and Transfer and Exchange

The Issuer will pay principal, interest and any premium on fully registered securities at the place or places designated by the Issuer for such purposes. The Issuer will make payment to the persons in whose names the debt securities are registered on the close of business on the record date for such interest. Any other payments will be made as set forth in the applicable prospectus supplement.

Holders may transfer or exchange fully registered securities at any office or agency maintained by the Issuer for such purposes, without the payment of any service charge except for any tax or governmental charge the Issuer is required to pay in connection with a transfer or exchange.

Upon surrender for registration of transfer of any security of any series in accordance with the terms of the indenture, the Issuer shall execute, and the trustee shall authenticate and deliver or make available for delivery, in the name of the designated transferee or transferees, one or more new securities of the same series, of any authorized denominations and of like tenor and aggregate principal amount.

If the securities of any series are to be redeemed, the Issuer is not required to:

Global Securities

Unless we inform you otherwise in an accompanying prospectus supplement, the debt securities of a series may be issued in whole or in part in the form of one or more global securities that will be deposited with, or on behalf of, a depositary identified in an accompanying prospectus supplement. Unless and until a global security is exchanged in whole or in part for the individual debt securities, a global security may not be transferred except as a whole by the depositary for such global security to a nominee of such depositary or by a nominee of such depositary to such depositary or another nominee of such depositary or by such depositary or any such nominee to a successor of such depositary or a nominee of such successor.

Defeasance

When we use the term defeasance, we mean discharge from some or all of the Issuer’s obligations under the indenture. Subject to certain additional conditions, if the Issuer irrevocably deposits with the trustee sufficient cash or government securities to pay the principal, interest, any premium and any other sums due to the stated maturity date or a redemption date of the debt securities of a particular series, then at the Issuer’s option:

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To exercise the defeasance option, the Issuer must deliver to the trustee an officer’s certificate and an opinion of counsel, each stating that all conditions precedent related to the defeasance have been complied with.

Concerning the Trustee

The trustee, The Bank of New York Mellon, has provided banking and investment services to us in the past and may do so in the future as a part of its regular business.

Governing Law

The indenture and the debt securities shall be construed in accordance with and governed by the laws of the State of New York.

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DESCRIPTION OF DEBT SECURITIES OF PFIZER INVESTMENT ENTERPRISES PTE. LTD.

In this “Description of Debt Securities of Pfizer Investment Enterprises Pte. Ltd.” section, references to the “Issuer” refer to Pfizer Investment Enterprises Pte. Ltd. and its successors, as the issuer of debt securities that may be offered hereunder.

The Issuer may offer debt securities in one or more series, which may be senior debt securities or subordinated debt securities and which may be convertible into another security. Any debt securities of the Issuer that may be offered hereunder will be fully and unconditionally guaranteed by Pfizer Inc. (“Parent”). See “—Guarantee of Debt Securities.” The Issuer is a private company limited by shares incorporated under the laws of the Republic of Singapore in order to facilitate the offering of debt securities. The Issuer is not an active trading company, is a “finance subsidiary” (as such term is used in Regulation S-X Rule 13-01) and has no assets or operations, and will have no assets or operations, other than as related to the issuance, administration and repayment of any debt securities that the Issuer has issued and may issue in the future that are fully and unconditionally guaranteed by Parent.

The following description briefly sets forth certain general terms and provisions of the debt securities. The particular terms of the debt securities offered by any prospectus supplement and the extent, if any, to which the following general terms and provisions may apply to the debt securities, will be described in an accompanying prospectus supplement. Unless otherwise specified in an accompanying prospectus supplement, the Issuer’s debt securities will be issued in one or more series under the indenture, dated as of May 19, 2023 (the “Pfizer Singapore indenture”) between the Issuer, Parent and The Bank of New York Mellon, as trustee. The Pfizer Singapore indenture is filed as an exhibit to the registration statement of which this prospectus forms a part, and any supplemental indenture will be filed as an exhibit to a document incorporated by reference herein, in connection with the issuance of any new series of debt securities offered and sold hereunder. In this “Description of Debt Securities of Pfizer Investment Enterprises Pte. Ltd.” section, we refer to the Pfizer Singapore indenture, as amended and supplemented by each supplemental indenture applicable to a series of debt securities issued thereunder and offered hereby, as an “indenture.” We urge you to read the Pfizer Singapore indenture and relevant supplemental indentures because these documents, and not the summary below, will define your rights as a holder of debt securities. Capitalized terms used in the summary will have the meanings specified in the indenture. The terms of the debt securities will include those that will be set forth in the indenture and those made a part of the indenture by the TIA. You should read the summary below, any accompanying prospectus supplement and the provisions of the indenture in their entirety before investing in the Issuer’s debt securities. The indenture will governed by the laws of the State of New York.

The aggregate principal amount of debt securities that may be issued under the indenture is unlimited. The prospectus supplement relating to any series of debt securities that the Issuer may offer will contain the specific terms of the debt securities. These terms may include, among others, the following:

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General

The Issuer may issue the debt securities in one or more series with the same or various maturities, at par or a premium or with original issue discount. Unless we inform you otherwise in a prospectus supplement, the Issuer may issue additional debt securities of a particular series without the consent of the holders of the debt securities of such series or any other series outstanding at the time of issuance. Any such additional debt securities, together with all other outstanding debt securities of that series, will constitute a single series of securities under the indenture.

We will describe in an accompanying prospectus supplement any other special considerations for any debt securities that are denominated in a currency or currency unit other than U.S. dollars. In addition, debt securities may be issued where the amount of principal and/or interest payable is determined by reference to one or more currency exchange rates, commodity prices, equity indices or other factors. Holders of such securities may receive a principal amount or a payment of interest that is greater than or less than the amount of principal or

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interest otherwise payable on such dates, depending upon the value of the applicable currencies, commodities, equity indices or other factors. Information as to the methods for determining the amount of principal or interest, if any, payable on any date, and the currencies, commodities, equity indices or other factors to which the amount payable on such date is linked will be described in an accompanying prospectus supplement.

United States federal income tax consequences and special considerations, if any, and general Singapore tax consequences applicable to any such series will be described in an accompanying prospectus supplement.

Unless otherwise specified in an accompanying prospectus supplement, the debt securities will be issued in fully registered form without coupons and in denominations of $2,000 and any integral multiple of $1,000 in excess thereof. Subject to the limitations provided in the indenture and in an accompanying prospectus supplement, debt securities that are issued in registered form may be transferred or exchanged at the designated corporate trust office of the trustee, without the payment of any service charge, other than any tax or other governmental charge payable in connection therewith.

Guarantee of Debt Securities

Parent will unconditionally and irrevocably guarantee the payment of all of the Issuer’s obligations under each series of debt securities offered hereunder and all other amounts owed under the indenture pursuant to the guarantee (the “Guarantee”) included in the indenture. If the Issuer defaults in the payment of the principal of, or premium, if any, or interest on, such debt securities when and as the same shall become due, whether upon maturity, acceleration, or otherwise, or any other amounts owed under the indenture, without the necessity of action by the trustee or any holder of such debt securities, Parent shall be required promptly and fully to make such payment. Upon a Parent Assumption (as defined herein), Parent shall cease to Guarantee any of the debt securities.

Consolidation, Merger or Sale

The Issuer and Parent will not consolidate with or merge into any other person or convey or transfer the properties and assets of the Issuer or Parent, as the case may be, as an entirety or substantially as an entirety, to any other person, unless:

Upon any consolidation of the Issuer or Parent, as the case may be, with, or merger of the Issuer or Parent, as the case may be, into, any other person or any conveyance or transfer of the properties and assets of the Issuer or Parent, as the case may be, as an entirety or substantially as an entirety in accordance with the foregoing requirements, the successor person will succeed to, and be substituted for, and may exercise every right and power of, the Issuer or Parent, as the case may be, under the indenture with the same effect as if such successor person were an original party to the indenture, and thereafter the Issuer or Parent, as the case may be, shall be relieved of all obligations and covenants under the indenture and the debt securities.

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Substitution of Parent as Issuer

Under the indenture, Parent has the right, at its option at any time, without the consent of any holders of any series of debt securities, to be substituted for, and assume the obligations of, the Issuer under each series of debt securities that are then outstanding under the indenture if, immediately after giving effect to such substitution, no event of default, and no event which, after notice or lapse of time or both, would become an event of default, has occurred and is continuing (other than a default or event of default that would be cured by such substitution), provided that Parent executes a supplemental indenture in which it agrees to be bound by the terms of each such series of debt securities and the indenture (the “Parent Assumption”). In the case of such Parent Assumption, (i) the Issuer will be relieved of any further obligations under the assumed series of debt securities and the indenture and (ii) Parent will be released from all obligations under the Guarantee, and will instead become the primary (and sole) obligor under such debt securities and the related indenture provisions. Following such Parent Assumption, references herein and in the indenture to the “Issuer” shall be deemed to instead refer to Parent.

Issuer Assets and Operations

The indenture contains a covenant requiring that, prior to a Parent Assumption, the Issuer shall remain a wholly-owned subsidiary of Parent (or any successor Parent under the covenant described under “—Consolidation, Merger or Sale”) at all times and shall not have any assets or operations that would cause the Issuer to fail to qualify as a “finance subsidiary” (as such term is used in Regulation S-X Rule 13-01) of Parent (or any such successor to Parent).

Modification of Indenture

Under the indenture, the Issuer, Parent and the applicable trustee may supplement the indenture for certain purposes which would not adversely affect the interests of the holders of debt securities of a series in any material respect without the consent of those holders. Under the indenture, the rights of the holders may be modified through a supplemental indenture if the holders of at least a majority in aggregate principal amount of the outstanding debt securities of all series affected by the modification (voting as one class) consent to it. No modification of the maturity date, principal or interest payment terms or premium payable on redemption, no modification of the currency for payment, no impairment of the right to sue for the enforcement of payment at the maturity of the debt security, no modification of any conversion rights, no modification reducing the percentage required for any such supplemental indenture or the percentage required for the waiver of compliance with certain provisions of the indenture or certain defaults, no adverse change in or release of the Guarantee (other than in accordance with the terms of the indenture) and no modification of the foregoing provisions or any other provisions relating to the waiver of past defaults or the waiver of certain covenants, is effective against any holder without its consent.

Events of Default

Each of the following will constitute an event of default under the indenture with respect to debt securities of any series:

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The supplemental indenture or the form of security for a particular series of debt securities may include additional events of default or changes to the events of default described above. The events of default applicable to a particular series of debt securities will be discussed in the prospectus supplement relating to such series. A default under our other indebtedness will not be a default under the indenture for the debt securities covered by this prospectus, and a default under one series of debt securities will not necessarily be a default under another series. The trustee may withhold notice to the holders of debt securities of any default (except for defaults that involve the Issuer’s failure to pay principal or interest) if it considers such withholding of notice to be in the best interests of the holders.

If an event of default with respect to outstanding debt securities of any series occurs and is continuing, then the trustee or the holders of at least 33% in principal amount of outstanding debt securities of that series may declare, in a written notice, the principal amount (or, if any of the securities of that series are original issue discount securities, such portion of the principal amount of such securities as specified in the terms thereof) plus accrued and unpaid interest on all debt securities of that series to be immediately due and payable. At any time after a declaration of acceleration with respect to debt securities of any series has been made and before a judgment or decree for the payment of money due has been obtained by the trustee, the event of default giving rise to such declaration of acceleration shall, without further act, be deemed to have been rescinded and annulled, if:

We refer you to the prospectus supplement relating to any series of debt securities that are discount securities for the particular provisions relating to acceleration of a portion of the principal amount of the discount securities upon the occurrence of an event of default.

If a default in the performance or breach of the indenture shall have occurred and be continuing, the holders of not less than a majority in principal amount of the outstanding securities of all series affected thereby, by notice to the trustee, may waive any past event of default or its consequences under the indenture. However, an event of default cannot be waived without the consent of the holders of each outstanding security of the series affected with respect to any series of securities in the following two circumstances:

The trustee is not obligated to exercise any of its rights or powers under the indenture at the request, order or direction of any holders, unless the holders offer the trustee security or indemnity reasonably satisfactory to the trustee. Holders of a majority in principal amount outstanding of any series of debt securities may, subject to certain limitations, direct the time, method and place of conducting any proceeding or any remedy available to the trustee, or exercising any power conferred upon the trustee, for such applicable series of debt securities.

The Issuer is required to deliver an annual officer’s certificate to the trustee stating whether it is in default in the performance and observance of any of the terms, provisions and conditions of the indenture, and, if the Issuer is in default, specifying all such defaults and the nature and status thereof.

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Payment and Transfer and Exchange

The Issuer will pay principal, interest and any premium on fully registered securities at the place or places designated by the Issuer for such purposes. The Issuer will make payment to the persons in whose names the debt securities are registered on the close of business on the record date for such interest. Any other payments will be made as set forth in the applicable prospectus supplement.

Holders may transfer or exchange fully registered securities at any office or agency maintained by the Issuer for such purposes, without the payment of any service charge except for any tax or governmental charge the Issuer is required to pay in connection with a transfer or exchange.

Upon surrender for registration of transfer of any security of any series in accordance with the terms of the indenture, the Issuer shall execute, and the trustee shall authenticate and deliver or make available for delivery, in the name of the designated transferee or transferees, one or more new securities of the same series, of any authorized denominations and of like tenor and aggregate principal amount.

If the securities of any series are to be redeemed, the Issuer is not required to:

Global Securities

Unless we inform you otherwise in an accompanying prospectus supplement, the debt securities of a series may be issued in whole or in part in the form of one or more global securities that will be deposited with, or on behalf of, a depositary identified in an accompanying prospectus supplement. Unless and until a global security is exchanged in whole or in part for the individual debt securities, a global security may not be transferred except as a whole by the depositary for such global security to a nominee of such depositary or by a nominee of such depositary to such depositary or another nominee of such depositary or by such depositary or any such nominee to a successor of such depositary or a nominee of such successor.

Defeasance

When we use the term defeasance, we mean discharge from some or all of the Issuer’s and Parent’s obligations under the indenture. Subject to certain additional conditions, if the Issuer irrevocably deposits, or causes to be deposited, with the trustee sufficient cash or government securities to pay the principal, interest, any premium and any other sums due to the stated maturity date or a redemption date of the debt securities of a particular series, then at the Issuer’s option:

To exercise the defeasance option, the Issuer must deliver to the trustee an officer’s certificate and an opinion of counsel, each stating that all conditions precedent related to the defeasance have been complied with.

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Concerning the Trustee

The trustee, The Bank of New York Mellon, has provided banking and investment services to us in the past and may do so in the future as a part of its regular business.

Governing Law

The indenture and the debt securities shall be construed in accordance with and governed by the laws of the State of New York.

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DESCRIPTION OF CAPITAL STOCK

General

The following description of certain terms of Parent’s capital stock does not purport to be complete and is subject to, and qualified in its entirety by reference to, Parent’s restated certificate of incorporation (the “Certificate of Incorporation”), Parent’s by-laws, as amended (the “By-Laws”), and the applicable provisions of the Delaware General Corporation Law (the “DGCL”). For more information on how you can obtain the Certificate of Incorporation and the By-Laws, see “Where You Can Find More Information.”

Common Stock

Under the Certificate of Incorporation, Parent is authorized to issue up to 12 billion shares of common stock, par value $0.05 per share. The common stock is not redeemable, does not have any conversion rights and is not subject to call. Holders of shares of common stock have no preemptive rights to maintain their percentage of ownership in future offerings or sales of Parent’s stock. Holders of shares of common stock have one vote per share in all elections of directors and on all other matters submitted to vote of Parent’s stockholders. The holders of common stock are entitled to receive dividends, if any, as and when may be declared from time to time by the Board of Directors of Parent out of funds legally available therefor. Upon liquidation, dissolution or winding up of Parent’s affairs, the holders of common stock will be entitled to participate equally and ratably, in proportion to the number of shares held, in Parent’s net assets available for distribution to holders of common stock. The shares of common stock currently outstanding are fully paid and nonassessable. As of February 15, 2024, there were 5,646,778,425 shares of Parent’s common stock outstanding. The common stock is traded on the NYSE under the trading symbol “PFE.”

The prospectus supplement relating to any common stock being offered will include specific terms relating to the offering.

Preferred Stock

Under the Certificate of Incorporation, Parent is authorized to issue up to 27 million shares of preferred stock, without par value. The preferred stock may be issued in one or more series, and the Board of Directors of Parent is expressly authorized (i) to fix the descriptions, powers, preferences, rights, qualifications, limitations, and restrictions with respect to any series of preferred stock and (ii) to specify the number of shares of any series of preferred stock. As of February 15, 2024, there were no shares of preferred stock issued and outstanding.

The prospectus supplement relating to any preferred stock being offered will include specific terms relating to the offering.

Anti-takeover Effects of the Certificate of Incorporation, By-laws and Delaware Law

Certificate of Incorporation and By-laws. Various provisions contained in the Certificate of Incorporation and the By-laws could delay or discourage some transactions involving an actual or potential change in control of Parent or a change in Parent’s management and may limit the ability of Parent’s stockholders to remove current management or approve transactions that Parent’s stockholders may deem to be in their best interests. Among other things, these provisions:

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Delaware Law. Parent is a Delaware corporation and consequently is also subject to certain anti-takeover provisions of the DGCL. Subject to certain exceptions, Section 203 of the DGCL prevents a publicly held Delaware corporation from engaging in a “business combination” with any “interested stockholder” for three years following the date that the person became an interested stockholder, unless (a) the interested stockholder attained such status with the approval of the corporation’s board of directors, (b) upon consummation of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, exclusive of shares owned by directors who are also officers and by certain employee stock plans or (c) at or subsequent to such time, the business combination is approved by the board of directors and authorized by the affirmative vote at a stockholders’ meeting, and not by written consent, of at least 66 2/3% of the outstanding voting stock which is not owned by the interested stockholder. A “business combination” includes, among other things, a merger or consolidation involving the corporation and the “interested stockholder” and the sale of more than 10% of the corporation’s assets. In general, an “interested stockholder” is any entity or person beneficially owning 15% or more of the corporation’s outstanding voting stock, and any entity or person affiliated with or controlling or controlled by such entity or person. Section 203 of the DGCL makes it more difficult for an interested stockholder to effect various business combinations with a corporation for a three-year period. This statute could prohibit or delay mergers or other takeover or change in control attempts not approved in advance by the Board of Directors of Parent, and, as a result, could discourage attempts to acquire us, which could depress the market price of our common stock.

DESCRIPTION OF OTHER SECURITIES

We will set forth, in the applicable prospectus supplement, a description of any warrants, depositary shares, purchase contracts, purchase units or guarantees (other than guarantees by Parent of debt securities issued by Pfizer Singapore) that may be offered pursuant to this prospectus.

SELLING SECURITYHOLDERS

Selling securityholders are persons or entities that, directly or indirectly, have acquired or will from time to time acquire from us, our securities in various private transactions. Such selling securityholders may be parties to registration rights agreements with us, or we otherwise may have agreed or will agree to register their securities for resale. The initial purchasers of our securities, as well as their transferees, pledgees, donees or successors, all of whom we refer to as “selling securityholders,” may from time to time offer and sell the securities pursuant to this prospectus and any applicable prospectus supplement.

The applicable prospectus supplement will set forth the name of each selling securityholder and the number of and type of securities beneficially owned by such selling securityholder that are covered by such prospectus

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supplement. The applicable prospectus supplement also will disclose whether any of the selling securityholders have held any position or office with, have been employed by or otherwise have had a material relationship with us during the three years prior to the date of the prospectus supplement.

PLAN OF DISTRIBUTION

Parent, Pfizer Singapore and any selling securityholder may sell the securities offered by this prospectus from time to time in one or more transactions, including without limitation:

In addition, Parent, Pfizer Singapore or any selling securityholder, may enter into derivative or hedging transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. In connection with such a transaction, the third parties may sell securities covered by and pursuant to this prospectus and an applicable prospectus supplement. If so, the third party may use securities borrowed from us or others to settle such sales and may use securities received from us to close out any related short positions. We may also loan or pledge securities covered by this prospectus and an applicable prospectus supplement to third parties, who may sell the loaned securities or, in an event of default in the case of a pledge, sell the pledged securities pursuant to this prospectus and the applicable prospectus supplement.

Parent, Pfizer Singapore and any selling securityholder may sell the securities offered by this prospectus at:

We will identify the specific plan of distribution, including any underwriters, dealers, agents or direct purchasers, and their compensation in a prospectus supplement.

LEGAL MATTERS

Margaret M. Madden, Parent’s Senior Vice President and Corporate Secretary, Chief Governance Counsel, will pass upon the validity of the securities for us. Ms. Madden beneficially owns, or has the right to acquire under our employee benefit plans, an aggregate of less than 1% of the outstanding shares of Parent’s common stock.

EXPERTS

The consolidated financial statements of Parent and subsidiary companies as of December 31, 2023 and 2022, and for each of the years in the three-year period ended December 31, 2023, and management’s assessment of the effectiveness of internal control over financial reporting as of December 31, 2023 have been incorporated by

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reference herein in reliance upon the report of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

The audit report on the effectiveness of internal control over financial reporting as of December 31, 2023, contains an explanatory paragraph that states the Company acquired Seagen on December 14, 2023, and management excluded from its assessment of the effectiveness of the Company’s internal control over financial reporting as of December 31, 2023, Seagen and its subsidiaries’ internal control over financial reporting associated with 22% of assets and 0.2% of revenues included in the consolidated financial statements of the Company as of and for the year ended December 31, 2023. The audit of internal control over financial reporting of the Company also excluded an evaluation of the internal control over financial reporting of Seagen and its subsidiaries.

WHERE YOU CAN FIND MORE INFORMATION

Parent files annual, quarterly and special reports, proxy statements and other information with the SEC. Parent’s SEC filings are available at the Internet website maintained by the SEC at http://www.sec.gov. The filings are also available on Parent’s website at http://www.pfizer.com.

THIS PROSPECTUS INCORPORATES DOCUMENTS BY REFERENCE WHICH ARE NOT PRESENTED IN OR DELIVERED WITH THIS PROSPECTUS. YOU SHOULD RELY ONLY ON THE INFORMATION CONTAINED IN THIS PROSPECTUS AND IN THE DOCUMENTS THAT WE HAVE INCORPORATED BY REFERENCE IN THIS PROSPECTUS. WE HAVE NOT AUTHORIZED ANYONE TO PROVIDE YOU WITH INFORMATION THAT IS DIFFERENT FROM OR IN ADDITION TO THE INFORMATION CONTAINED IN THIS PROSPECTUS AND IN THE DOCUMENTS THAT WE HAVE INCORPORATED BY REFERENCE IN THIS PROSPECTUS. WE TAKE NO RESPONSIBILITY FOR, AND CAN PROVIDE NO ASSURANCE AS TO THE RELIABILITY OF, ANY OTHER INFORMATION THAT OTHERS MAY GIVE YOU.

We incorporate information into this prospectus by reference, which means that we disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, except to the extent superseded by information contained in this prospectus or by information contained in documents filed with the SEC after the date of this prospectus. This prospectus incorporates by reference the documents set forth below that have been previously filed with the SEC; provided, however, that we are not incorporating any documents or information deemed to have been furnished rather than filed in accordance with SEC rules. These documents contain important information about us and our financial condition.

We also incorporate by reference any future filings made by Parent with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act between the date of this prospectus and the date all of the securities offered by this prospectus are sold or the offering is otherwise terminated, with the exception of any information furnished under Item 2.02 and Item 7.01 of Form 8-K, which is not deemed filed and which is not incorporated

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by reference in this prospectus. Any such filings shall be deemed to be incorporated by reference and to be a part of this prospectus from the respective dates of filing of those documents.

We will provide without charge upon written or oral request to each person, including any beneficial owner, to whom a prospectus is delivered, a copy of any and all of the documents which are incorporated by reference in this prospectus but not delivered with this prospectus (other than exhibits unless such exhibits are specifically incorporated by reference in such documents). You may request a copy of these documents by writing or telephoning us at:

Senior Vice President and Corporate Secretary

Pfizer Inc.

66 Hudson Boulevard East,

New York, New York 10001-2192

(212) 733-2323

The information contained on our website, our Facebook, Youtube and LinkedIn Pages or our Twitter accounts does not, and shall not be deemed to, constitute a part of this prospectus.

ENFORCEMENT OF CIVIL LIABILITIES AND SERVICE OF PROCESS

The Pfizer Singapore indenture and debt securities will be governed by New York law. Pfizer Singapore is a private company limited by shares incorporated under the laws of the Republic of Singapore and has no assets or operations, and will have no assets or operations, other than as related to the issuance, administration and repayment of any debt securities it has issued and may issue in the future that are fully and unconditionally guaranteed by Parent. In addition, some of Pfizer Singapore’s directors, and all or a substantial portion of the assets of Pfizer Singapore, are, or will be located, outside the United States. As a result, it may not be possible for investors to effect service of process within the United States upon Pfizer Singapore or to enforce against Pfizer Singapore in United States courts, judgments obtained in such courts predicated upon the civil liability provisions of the federal securities laws of the United States. Pfizer Singapore has, however, agreed to appoint Parent to be its authorized agent for service of process with respect to actions based on offers and sales of debt securities made in the United States and other violations of United States securities laws.

There is uncertainty as to whether judgments of courts in the United States based upon the civil liability provisions of the federal securities laws of the United States would be recognized or enforceable in Singapore courts, and there is doubt as to whether Singapore courts would enter judgments in original actions brought in Singapore courts based solely upon the civil liability provisions of the federal securities laws of the United States. A final and conclusive judgment in the federal or state courts of the United States under which a fixed sum of money is payable, other than a sum payable in respect of taxes, fines, penalties or similar charges, may be subject to enforcement proceedings as a debt in the courts of Singapore under the common law.

Civil liability provisions of the federal and state securities law of the United States permit the award of punitive damages against Pfizer Singapore and its directors. Singapore courts may not recognize or enforce judgments against Pfizer Singapore and its directors to the extent that the judgment is punitive or penal. It is uncertain as to whether a judgment of the courts of the United States under civil liability provisions of the federal securities law of the United States would be determined by the Singapore courts to be or not be punitive or penal in nature. The Singapore courts also may not recognize or enforce a foreign judgment if the foreign judgment is inconsistent with a prior local judgment, contravenes public policy, or amounts to the direct or indirect enforcement of a foreign penal, revenue or other public law.

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PART II

The following table sets forth the estimated fees and expenses payable in connection with the registration of the securities registered hereby:

Pfizer Inc.

Section 145 of the DGCL permits a corporation to indemnify any person who is or has been a director, officer, employee or agent of the corporation or who is or has been serving as director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise at the request of the corporation, against all liability and expenses (including, but not limited to, attorneys’ fees and disbursements and amounts paid in settlement or in satisfaction of judgments or as fines or penalties) incurred or paid in connection with any claim, action, suit or proceeding, whether civil, criminal, administrative, investigative or otherwise, in which he/she may be involved by reason of the fact that he/she served or is serving in these capacities, if he/she acted in good faith and in a manner he/she reasonably believed to be in or not opposed to the best interest of the corporation and, with respect to any criminal action or proceeding, had no cause to believe his/her conduct was unlawful. In the case of a claim, action, suit or proceeding made or brought by or in the right of the corporation to procure a judgment in its favor, the corporation shall not indemnify such person in respect of any claim, issue or matter as to which such person has been adjudged to be liable to the corporation for negligence or misconduct in the performance of his/her duty to the corporation, except for such expenses as the court may allow. Any such person who has been wholly successful on the merits or otherwise with respect to any such claim, action, suit or proceeding or with respect to any claim, issue or matter therein, shall be indemnified against expenses (including attorneys’ fees) actually and reasonably incurred in connection therewith or resulting therefrom.

Section 102(b)(7) of the DGCL provides that a corporation may eliminate or limit the personal liability of a director or officer to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director or officer, provided that such provision shall not eliminate or limit the liability of (i) a director or officer for any breach of the director’s or officer’s duty of loyalty to the corporation or its stockholders, (ii) a director or officer for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) a director under Section 174 of the DGCL, (iv) a director or officer for any transaction from which the director or officer derived an improper personal benefit, (v) an officer in any action by or in the right of the corporation or (vi) a director or officer for any act or omission occurring prior to the date when such provision becomes effective.

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Pursuant to Article V, Section 1 of the By-Laws, Parent will indemnify and hold harmless directors and officers who were or are made or are threatened to be made a party or are otherwise involved in any action, suit or proceeding, whether civil, criminal, administrative or investigative, to the fullest extent permitted by applicable law as it presently exists or is amended. Parent has entered into agreements with its directors and certain of its officers requiring Parent to indemnify such persons to the fullest extent permitted by the By-Laws. Parent also maintains insurance coverage relating to certain liabilities of directors and officers.

Pfizer Investment Enterprises Pte. Ltd.

Under Singapore law, any provision that purports to exempt any officer (including a director) of a company (to any extent) from any liability that would otherwise attach to him or her in connection with any negligence, default, breach of duty or breach of trust in relation to the company is void.

Further any provision by which a company directly or indirectly provides an indemnity (to any extent) for an officer (including a director) of the company against any liability attaching to him or her in connection with any negligence, default, breach of duty or breach of trust in relation to the company is void, except as permitted by section 172A or section 172B of the Companies Act 1967 of Singapore (“Companies Act”):

The Exhibits to this registration statement are listed in the Exhibit Index below and are incorporated by reference in this prospectus.

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provided, however, that paragraphs (a)1(i), (a)1(ii) and (a)1(iii) of this section do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement or is contained in a form of prospectus filed pursuant to Rule 424(b) under the Securities Act of 1933 that is part of the registration statement.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, Pfizer Inc. certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York, State of New York, on February 23, 2024.

Each person whose signature appears below hereby constitutes and appoints Douglas M. Lankler and Margaret M. Madden and each of them, his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) and supplements to this registration statement, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, and hereby grants to such attorneys-in-fact and agents, full power and authority to do and perform each and every act and thing requisite and necessary to be done, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or either of them, or their or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, Pfizer Investment Enterprises Pte. Ltd. certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the Republic of Singapore, on February 23, 2024.

Each person whose signature appears below hereby constitutes and appoints Brian James Mc Mahon and Dana Alan Ritchey and each of them, his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) and supplements to this registration statement, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, and hereby grants to such attorneys-in-fact and agents, full power and authority to do and perform each and every act and thing requisite and necessary to be done, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or either of them, or their or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

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Exhibit 5.1

February 23, 2024

Pfizer Inc.

66 Hudson Boulevard East

New York, NY 10001-2192

Pfizer Investment Enterprises Pte. Ltd.

Registration Statement on Form S-3

Ladies and Gentlemen:

Attorneys under my supervision and I have acted as counsel for Pfizer Inc., a Delaware corporation (the “Company”) and Pfizer Investment Enterprises Pte. Ltd., a Singapore private limited company (“Pfizer Singapore”), which is a wholly-owned subsidiary of the Company and a co-registrant on the registration statement on Form S-3 (the “Registration Statement”), to be filed on the date hereof by the Company and Pfizer Singapore with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”). The Registration Statement relates to the issuance and sale by the Company from time to time, pursuant to Rule 415 of the General Rules and Regulations of the Commission promulgated (a) under the Securities Act (the “Rules and Regulations”), of (i) shares of common stock, par value $0.05 per share, of the Company (“Common Stock”), (ii) shares of preferred stock, without par value, of the Company (“Preferred Stock”), which may be issued in one or more series, (iii) depositary receipts (the “Receipts”) representing fractional shares of Preferred Stock, which are called depositary shares (the “Depositary Shares”) and which may be issued pursuant to one or more depositary agreements (each, a “Depositary Agreement”) proposed to be entered into between the Company and one or more bank or trust companies to be named in the applicable Depositary Agreement (each, a “Bank Depositary”), (iv) debt securities of the Company (“Company Debt Securities”), which may be issued in one or more series under an indenture, dated as of September 7, 2018 (the “Company Indenture”), between the Company and The Bank of New York Mellon, as trustee (the “Trustee”), (v) warrants to purchase shares of Common Stock, shares of Preferred Stock or Company Debt Securities (“Warrants”), which may be issued pursuant to one or more warrant agreements (each, a “Warrant Agreement”) proposed to be entered into by the Company and one or more warrant agents to be named therein, (vi) purchase contracts (“Purchase Contracts”) obligating the holders thereof to purchase from the Company, and the Company to sell to such holders, shares of Common Stock, shares of Preferred Stock or Company Debt Securities at a future date or dates, which may be issued pursuant to one or more purchase contract agreements (each, a “Purchase Contract Agreement”) proposed to be entered into by the Company and one or more purchase contract agents to be named therein, (vii) purchase units of the Company (“Purchase Units”), which may be issued pursuant to one or more agreements (each, a “Purchase Unit Agreement”) proposed to be entered into by the Company and one or more purchase unit agents to be named therein, (viii) such

Pfizer Inc.

Pfizer Investment Enterprises Pte. Ltd.

February 23, 2024

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indeterminate number of shares of Common Stock, Preferred Stock or Depositary Shares and indeterminate amount of Company Debt Securities as may be issued upon conversion, exchange or exercise, as applicable, of any Preferred Stock, Depositary Shares, Company Debt Securities, Warrants or settlement of any Purchase Contracts or Purchase Units, including such shares of Common Stock or Preferred Stock as may be issued pursuant to anti-dilution adjustments determined at the time of offering (collectively, “Indeterminate Securities”); and (b) the issuance and sale by Pfizer Singapore of debt securities of Pfizer Singapore (the “Singapore Debt Securities” and, together with the Company Debt Securities, the “Debt Securities”), which will be guaranteed by the Company (the “Guarantee”) and which may be issued in one or more series under an indenture, dated as of May 19, 2023 (the “Singapore Indenture”), among Pfizer Singapore, the Company and the Trustee. The Common Stock, Preferred Stock, Depositary Shares, Company Debt Securities, Warrants, Purchase Contracts, Purchase Units, Indeterminate Securities, Singapore Debt Securities and the Guarantee offered pursuant to the Registration Statement are collectively referred to herein as the “Securities.”

This opinion is being furnished in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act.

In rendering the opinions stated herein, attorneys under my supervision and/or I have examined and relied upon the following:

(a) the Registration Statement;

(b) the Company Indenture;

(c) the Singapore Indenture;

(d) a copy of the Restated Certificate of Incorporation of the Company, dated December 14, 2020 (as so amended, the “Certificate of Incorporation”), certified by the Secretary of State of the State of Delaware as of the date hereof;

(e) a copy of the By-laws of the Company (the “By-laws”), as amended and in effect as of the date hereof; and

(f) a copy of certain resolutions of the Board of Directors of the Company.

Attorneys under my supervision and/or I have also examined originals or copies, certified or otherwise identified to our satisfaction, of such records of the Company and Pfizer Singapore and such agreements, certificates and receipts of public officials, certificates of officers or other representatives of the Company and Pfizer Singapore and others, and such other documents as we have deemed necessary or appropriate as a basis for the opinions stated below.

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Pfizer Investment Enterprises Pte. Ltd.

February 23, 2024

Page 3

In our examination, attorneys under my supervision and/or I have assumed the genuineness of all signatures, including electronic signatures, the legal capacity and competency of all natural persons, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as facsimile, electronic, certified or photocopied copies, and the authenticity of the originals of such copies. As to any facts relevant to the opinions stated herein that attorneys under my supervision and I did not independently establish or verify, we have relied upon statements and representations of officers and other representatives of the Company and Pfizer Singapore and others and of public officials.

I am admitted to the bar in the State of New York, and I do not express any opinion as to the laws of any jurisdiction other than (i) the laws of the State of New York, and (ii) the General Corporation Law of the State of Delaware (the “DGCL”) (all of the foregoing being referred to as “Opined-on Law”).

As used herein, “Transaction Documents” means the Company Indenture, the Singapore Indenture and the supplemental indentures or officer’s certificates establishing the terms of the Debt Securities pursuant thereto, the Warrant Agreements, the Purchase Contract Agreements, the Purchase Unit Agreements and any applicable underwriting or purchase agreement.

The opinions stated in paragraphs 1 through 9 below presume that all of the following (collectively, the “general conditions”) shall have occurred prior to the issuance of the Securities referred to therein: (i) the Registration Statement, as finally amended (including all necessary post-effective amendments), has become effective under the Securities Act; (ii) an appropriate prospectus supplement or term sheet with respect to such Securities has been prepared, delivered and filed in compliance with the Securities Act and the applicable Rules and Regulations; (iii) the applicable Transaction Documents shall have been duly authorized, executed and delivered by the Company, Pfizer Singapore, to the extent applicable, and the other parties thereto, including, if such Securities are to be sold or otherwise distributed pursuant to a firm commitment underwritten offering, the underwriting agreement or purchase agreement with respect thereto; (iv) the Board of Directors of the Company or the applicable governing body of Pfizer Singapore, to the extent applicable, including any duly authorized committee thereof, shall have taken all necessary corporate action to approve the issuance and sale of such Securities and related matters and appropriate officers of the Company and Pfizer Singapore, to the extent applicable, have taken all related action as directed by or under the direction of the Board of Directors of the Company, the applicable governing body of Pfizer Singapore, to the extent applicable, or any duly authorized committee thereof; and (v) the terms of the applicable Transaction Documents and the issuance and sale of such Securities have been duly established in conformity with the Certificate of Incorporation of the Company or the constitution of Pfizer Singapore, to the extent applicable, so as not to violate any applicable law, the Certificate of Incorporation of the Company, the By-laws of the Company or the constitution of Pfizer Singapore, to the extent applicable, or result in a default under or breach of any agreement or instrument binding upon the Company or Pfizer Singapore, to the extent applicable, and so as to comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over the Company or Pfizer Singapore, to the extent applicable.

Based upon the foregoing and subject to the qualifications and assumptions stated herein, I am of the opinion that:

Pfizer Inc.

Pfizer Investment Enterprises Pte. Ltd.

February 23, 2024

Page 4

1. With respect to any shares of Common Stock (including any Common Stock duly issued upon conversion, exchange or exercise of any preferred stock, depositary shares, debt securities or warrants) offered by the Company, including any Indeterminate Securities constituting Common Stock (the “Offered Common Stock”), when (a) the general conditions shall have been satisfied, (b) if the Offered Common Stock is to be certificated, certificates in the form required under the DGCL representing the shares of Offered Common Stock are duly executed and countersigned and (c) the shares of Offered Common Stock are registered in the Company’s share registry and delivered upon payment of the agreed-upon consideration therefor, the shares of Offered Common Stock, when issued and sold or otherwise distributed in accordance with the provisions of the applicable Transaction Document, will be duly authorized by all requisite corporate action on the part of the Company under the DGCL and validly issued, fully paid and nonassessable, provided that the consideration therefor is not less than $0.05 per share of Common Stock.

2. With respect to the shares of any series of Preferred Stock (including any preferred stock duly issued upon conversion, exchange or exercise of any preferred stock, depositary shares, debt securities or warrants) offered by the Company, including any Indeterminate Securities constituting Preferred Stock of such series (the “Offered Preferred Stock”), when (a) the general conditions shall have been satisfied, (b) the Board of Directors of the Company, or a duly authorized committee thereof, has duly adopted a Certificate of Designations for the Offered Preferred Stock in accordance with the DGCL (the “Certificate”), (c) the filing of the Certificate with the Secretary of State of the State of Delaware has duly occurred, (d) if the Offered Preferred Stock is to be certificated, certificates in the form required under the DGCL representing the shares of Offered Preferred Stock are duly executed and countersigned and (e) the shares of Offered Preferred Stock are registered in the Company’s share registry and delivered upon payment of the agreed-upon consideration therefor, the shares of Offered Preferred Stock, when issued and sold or otherwise distributed in accordance with the provisions of the applicable Transaction Document, will be duly authorized by all requisite corporate action on the part of the Company under the DGCL and validly issued, fully paid and nonassessable.

3. With respect to any Depositary Shares offered by the Company, including any Indeterminate Securities constituting Depositary Shares (the “Offered Depositary Shares”), when (a) the general conditions shall have been satisfied, (b) the Preferred Stock relating to such Offered Depositary Shares has been duly authorized for issuance by the Company; (c) the Offered Depositary Shares have been duly executed, delivered, countersigned, issued and sold in accordance with the provisions of the applicable Depositary Agreement, and the Offered Depositary Shares have been delivered to the Bank Depositary for deposit in accordance with the applicable Depositary Agreement; and (d) the Receipts evidencing the Depositary Shares have been duly issued against deposit of the related shares of Preferred Stock with the Bank Depositary in accordance with the applicable Depositary Agreement, such Depositary Agreement will constitute a legally valid and binding obligation of the Company, enforceable against the Company in accordance with its respective terms under the laws of the State of New York.

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Pfizer Investment Enterprises Pte. Ltd.

February 23, 2024

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4. With respect to any series of Company Debt Securities offered by the Company, including any Indeterminate Securities constituting Company Debt Securities of such series (the “Company Offered Debt Securities”), when (a) the general conditions shall have been satisfied, (b) the Company Indenture has been duly qualified under the Trust Indenture Act of 1939 (the “TIA”); (c) the issuance, sale and terms of the Company Offered Debt Securities and related matters have been approved and established in conformity with the applicable Transaction Documents and (d) the certificates evidencing the Company Offered Debt Securities have been issued in a form that complies with the provisions of the applicable Transaction Documents and have been duly executed and authenticated in accordance with the provisions of the Company Indenture and any other applicable Transaction Documents and issued and sold or otherwise distributed in accordance with the provisions of the applicable Transaction Document upon payment of the agreed-upon consideration therefor, the Company Offered Debt Securities will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their respective terms under the laws of the State of New York.

5. With respect to any Warrants offered by the Company (the “Offered Warrants”), when (a) the general conditions shall have been satisfied, (b) the Common Stock, Preferred Stock and/or Company Debt Securities for which the Offered Warrants are exercisable have been duly authorized for issuance by the Company and (c) certificates evidencing the Offered Warrants have been duly executed, delivered and countersigned in accordance with the provisions of the applicable Warrant Agreement, the Offered Warrants, when issued and sold or otherwise distributed in accordance with the provisions of the applicable Transaction Document upon payment of the agreed-upon consideration therefor, will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their respective terms under the laws of the State of New York.

6. With respect to any Purchase Contracts offered by the Company (the “Offered Purchase Contracts”), when (a) the general conditions shall have been satisfied, (b) the Common Stock, Preferred Stock and/or Company Debt Securities relating to such Offered Purchase Contracts have been duly authorized for issuance by the Company and (c) the Offered Purchase Contracts have been duly executed, delivered and countersigned in accordance with the provisions of the applicable Purchase Contract Agreement, the Offered Purchase Contracts, when issued and sold or otherwise distributed in accordance with the provisions of the applicable Transaction Document upon payment of the agreed-upon consideration therefor, will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their respective terms under the laws of the State of New York.

7. With respect to any Purchase Units offered by the Company (the “Offered Purchase Units”), when (a) the general conditions shall have been satisfied, (b) the underlying securities included in such Offered Purchase Units have been duly authorized for issuance by the Company and (c) certificates evidencing the Offered Purchase Units have been duly executed, delivered and countersigned in accordance with the provisions of the applicable Purchase Unit Agreement, the Offered Purchase Units, when issued and sold or otherwise distributed in accordance with the provisions of the applicable Transaction Document upon payment of the agreed-upon consideration therefor, will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their respective terms under the laws of the State of New York.

Pfizer Inc.

Pfizer Investment Enterprises Pte. Ltd.

February 23, 2024

Page 6

8. With respect to any series of Singapore Debt Securities offered by Pfizer Singapore (the “Singapore Offered Debt Securities”), when (a) the general conditions shall have been satisfied, (b) the Singapore Indenture has been duly qualified under the TIA; (c) the issuance, sale and terms of the Singapore Offered Debt Securities and related matters have been approved and established in conformity with the applicable Transaction Documents and (d) the certificates evidencing the Singapore Offered Debt Securities have been issued in a form that complies with the provisions of the applicable Transaction Documents and have been duly executed and authenticated in accordance with the provisions of the Singapore Indenture and any other applicable Transaction Documents and issued and sold or otherwise distributed in accordance with the provisions of the applicable Transaction Document upon payment of the agreed-upon consideration therefor, the Singapore Offered Debt Securities will constitute valid and binding obligations of Pfizer Singapore, enforceable against Pfizer Singapore in accordance with their respective terms under the laws of the State of New York.

9. With respect to any Guarantee of any series of Singapore Offered Debt Securities by the Company (the “Singapore Offered Guarantees”), when (a) the general conditions shall have been satisfied, (b) the Singapore Indenture has been duly qualified under the TIA, (c) the issuance, sale and terms of the Singapore Offered Guarantees and related matters have been approved and established in conformity with the applicable Transaction Documents, (d) certificates (if any) evidencing the Singapore Offered Guarantees and the certificates evidencing the Singapore Offered Debt Securities guaranteed thereby have been duly executed and, if applicable, authenticated in accordance with the provisions of the Singapore Indenture and any other applicable Transaction Documents and (e) such Singapore Offered Debt Securities have been issued and sold or otherwise distributed in accordance with the provisions of the applicable Transaction Document upon payment of the agreed-upon consideration therefor, the Singapore Offered Guarantees will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their respective terms under the laws of the State of New York.

The opinions stated herein are subject to the following qualifications:

(a) I do not express any opinion to the effect on the opinions stated herein of any bankruptcy, insolvency, reorganization, moratorium, fraudulent transfer, preference and other similar laws or governmental orders affecting creditors’ rights generally, and the opinions stated herein are limited by such laws and by general principles of equity (regardless of whether enforcement is sought in equity or at law);

(b) I do not express any opinion with respect to any law, rule or regulation that is applicable to any party to any of the Transaction Documents or the transactions contemplated thereby solely because such law, rule or regulation is part of a regulatory regime applicable to any such party or any of its affiliates as a result of the specific assets or business operations of such party or such affiliates;

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Pfizer Investment Enterprises Pte. Ltd.

February 23, 2024

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(c) except to the extent expressly stated in the opinions contained herein, I have assumed that each of the Transaction Documents constitutes the valid and binding obligation of each party to such Transaction Document, enforceable against such party in accordance with its terms;

(d) I do not express any opinion with respect to the enforceability of any provision contained in any Transaction Document relating to any indemnification, contribution, non-reliance, exculpation, release, limitation or exclusion of remedies, waiver or other provisions having similar effect that may be contrary to public policy or violative of federal or state securities laws, rules or regulations, or to the extent any such provision purports to, or has the effect of, waiving or altering any statute of limitations;

(e) I do not express any opinion with respect to the enforceability of any provision of any Transaction Document to the extent that such section purports to bind any party thereto to the exclusive jurisdiction of any particular federal court or courts;

(f) I call to your attention that irrespective of the agreement of the parties to any Transaction Document, a court may decline to hear a case on grounds of forum non conveniens or other doctrine limiting the availability of such court as a forum for resolution of disputes; in addition, I call to your attention that I do not express any opinion with respect to the subject matter jurisdiction of the federal courts of the United States of America in any action arising out of or relating to any Transaction Document;

(g) I have assumed that any agent of service will have accepted appointment as agent to receive service of process and call to your attention that I do not express any opinion if and to the extent such agent shall resign such appointment. Further, I do not express any opinion with respect to the irrevocability of the designation of such agent to receive service of process;

(h) I have assumed that the choice of New York law to govern the Company Indenture and the Singapore Indenture and any supplemental indenture thereto is a valid and legal provision;

(i) I have assumed that the laws of the State of New York will be chosen to govern any Depositary Agreements, Warrant Agreements, Purchase Contract Agreements and Purchase Unit Agreements and that such choice is and will be a valid and legal provision;

(j) I have assumed that the Company Indenture and the Singapore Indenture, in each case, will be duly authorized, executed and delivered by the Trustee in substantially the form reviewed by us, and that any Debt Securities, Warrants, Purchase Contracts and Purchase Units that may be issued will be manually authenticated, signed or countersigned, as the case may be, by duly authorized officers of any trustee, warrant agent, purchase contract agent and purchase unit agent, as the case may be;

Pfizer Inc.

Pfizer Investment Enterprises Pte. Ltd.

February 23, 2024

Page 8

(k) I do not express any opinion with respect to the enforceability of any provisions contained in the Singapore Offered Guarantees or the related Transaction Documents to the extent that such provisions provide that the obligations of the Company are absolute and unconditional irrespective of the enforceability or genuineness of the Singapore Indenture or the effect thereof on the opinions herein stated;

(l) I do not express any opinion with respect to the enforceability of any provisions contained in the Singapore Offered Guarantees or the related Transaction Documents to the extent that such provisions limit the obligation of the Company under the Singapore Indenture or any right of contribution of any party with respect to the Singapore Offered Guarantees;

(m) I call to your attention that the opinions stated herein are subject to possible judicial action giving effect to governmental actions or laws of jurisdictions other than those with respect to which I express my opinion;

(n) I do not express any opinion with respect to the enforceability of any provision contained in any Transaction Document providing for indemnity by any party thereto against any loss in obtaining the currency due to such party under any Transaction Document from a court judgment in another currency;

(o) I have assumed that the choice of a currency other than U.S. dollars as the currency in which any Securities may be denominated does not contravene any exchange control or other laws of the jurisdiction of any such currency, and further I call to your attention that a court may not award a judgment in any currency other than U.S. dollars; and

(p) to the extent that any opinion relates to the enforceability of the choice of New York law and choice of New York forum provisions contained in any Transaction Document, the opinions stated herein are subject to the qualification that such enforceability may be subject to, in each case, (i) the exceptions and limitations in New York General Obligations Law sections 5-1401 and 5-1402 and (ii) principles of comity and constitutionality.

In addition, in rendering the foregoing opinions I have assumed that:

(a) Pfizer Singapore (i) is duly formed and is validly existing and in good standing, (ii) has requisite legal status and legal capacity under the laws of Singapore and (iii) has complied and will comply with all aspects of the laws of Singapore in connection with the transactions contemplated by, and the performance of its obligations under, any Transaction Document to which Pfizer Singapore is a party;

(b) Pfizer Singapore has the applicable power and authority to execute, deliver and perform all its obligations under any Transaction Document to which Pfizer Singapore is a party;

(c) neither the execution and delivery by the Company and Pfizer Singapore of the Transaction Documents to which the Company or Pfizer Singapore is a party, as the case may be, nor the performance by the Company and Pfizer Singapore of their respective obligations under each of the Transaction Documents, including the issuance and sale of the applicable Securities: (i) conflicts or will conflict with the Certificate of Incorporation of the Company, the By-laws of

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Pfizer Investment Enterprises Pte. Ltd.

February 23, 2024

Page 9

the Company or the constitution of Pfizer Singapore, to the extent applicable, (ii) constitutes or will constitute a violation of, or a default under, any lease, indenture, agreement or other instrument to which the Company or Pfizer Singapore or their respective property is subject, (iii) contravened or will contravene any order or decree of any governmental authority to which the Company or Pfizer Singapore or their respective property is subject, or (iv) violates or will violate any law, rule or regulation to which the Company or Pfizer Singapore or their respective property is subject (except that I do not make the assumption set forth in this clause (iv) with respect to the Opined-on Law); and

(d) neither the execution and delivery by the Company or Pfizer Singapore of any Transaction Document to which it is a party nor the enforceability of each of the Transaction Documents against the Company or Pfizer Singapore requires or will require the consent, approval, licensing or authorization of, or any filing, recording or registration with, any governmental authority under any law, rule or regulation of any jurisdiction.

I hereby consent to the reference to my name under the heading “Legal Matters” in the prospectus forming part of the Registration Statement. I also hereby consent to the filing of this opinion with the Commission as an exhibit to the Registration Statement. In giving this consent, I do not thereby admit that I am within the category of persons whose consent is required under Section 7 of the Securities Act or the Rules and Regulations. This opinion is expressed as of the date hereof unless otherwise expressly stated, and I disclaim any undertaking to advise you of any subsequent changes in the facts stated or assumed herein or of any subsequent changes in applicable laws.

Exhibit 23.2

KPMG LLP

345 Park Avenue

New York, NY 10154-0102 

Consent of Independent Registered Public Accounting Firm

We consent to the use of our reports dated February 22, 2024, with respect to the consolidated financial statements of Pfizer Inc. and Subsidiary Companies, and the effectiveness of internal control over financial reporting, incorporated herein by reference, and to the reference to our firm under the heading “Experts” in the prospectus.

/s/ KPMG LLP

New York, New York

February 23, 2024

Exhibit 25.1

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM T-1

STATEMENT OF ELIGIBILITY

UNDER THE TRUST INDENTURE ACT OF 1939

OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE

THE BANK OF NEW YORK MELLON

(Exact name of trustee as specified in its charter)

PFIZER INC.

(Exact name of registrant as specified in its charter)

Debt Securities

(Title of the indenture securities)

Yes.

If the obligor is an affiliate of the trustee, describe each such affiliation.

None.

Exhibits identified in parentheses below, on file with the Commission, are incorporated herein by reference as an exhibit hereto, pursuant to Rule 7a-29 under the Trust Indenture Act of 1939 (the “Act”).

- 2 -

- 3 -

SIGNATURE

Pursuant to the requirements of the Act, the Trustee, The Bank of New York Mellon, a corporation organized and existing under the laws of the State of New York, has duly caused this statement of eligibility to be signed on its behalf by the undersigned, thereunto duly authorized, all in the City of New York, and State of New York, on the 2nd day of February, 2024.

- 4 -

EXHIBIT 7

Consolidated Report of Condition of

THE BANK OF NEW YORK MELLON

of 240 Greenwich Street, New York, N.Y. 10286

And Foreign and Domestic Subsidiaries,

a member of the Federal Reserve System, at the close of business December 31, 2023, published in accordance with a call made by the Federal Reserve Bank of this District pursuant to the provisions of the Federal Reserve Act.

- 5 -

- 6 -

I, Dermot McDonogh, Chief Financial Officer of the above-named bank do hereby declare that this Report of Condition is true and correct to the best of my knowledge and belief.

We, the undersigned directors, attest to the correctness of this statement of resources and liabilities. We declare that it has been examined by us, and to the best of our knowledge and belief has been prepared in conformance with the instructions and is true and correct.

- 7 -

Exhibit 25.2

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM T-1

STATEMENT OF ELIGIBILITY

UNDER THE TRUST INDENTURE ACT OF 1939

OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE

THE BANK OF NEW YORK MELLON

(Exact name of trustee as specified in its charter)

PFIZER INVESTMENT ENTERPRISES PTE. LTD.

(Exact name of obligor as specified in its charter)

PFIZER INC.

(Exact name of registrant as specified in its charter)

Debt Securities

and Guarantees of Debt Securities

(Title of the indenture securities)

1. General information. Furnish the following information as to the Trustee:

Yes.

If the obligor is an affiliate of the trustee, describe each such affiliation.

None.

Exhibits identified in parentheses below, on file with the Commission, are incorporated herein by reference as an exhibit hereto, pursuant to Rule 7a-29 under the Trust Indenture Act of 1939 (the “Act”).

- 2 -

- 3 -

SIGNATURE

Pursuant to the requirements of the Act, the Trustee, The Bank of New York Mellon, a corporation organized and existing under the laws of the State of New York, has duly caused this statement of eligibility to be signed on its behalf by the undersigned, thereunto duly authorized, all in the City of New York, and State of New York, on the 2nd day of February, 2024.

- 4 -

EXHIBIT 7

Consolidated Report of Condition of

THE BANK OF NEW YORK MELLON

of 240 Greenwich Street, New York, N.Y. 10286

And Foreign and Domestic Subsidiaries,

a member of the Federal Reserve System, at the close of business December 31, 2023, published in accordance with a call made by the Federal Reserve Bank of this District pursuant to the provisions of the Federal Reserve Act.

- 5 -

- 6 -

I, Dermot McDonogh, Chief Financial Officer of the above-named bank do hereby declare that this Report of Condition is true and correct to the best of my knowledge and belief.

We, the undersigned directors, attest to the correctness of this statement of resources and liabilities. We declare that it has been examined by us, and to the best of our knowledge and belief has been prepared in conformance with the instructions and is true and correct.

- 7 -

Exhibit 107

Calculation of Filing Fee Table

S-3

(Form Type)

Pfizer Inc.

Pfizer Investment Enterprises Pte. Ltd.

(Exact Name of Registrant as Specified in its Charter)

Table 1: Newly Registered Securities and Carry Forward Securities