Filed pursuant to Rule 424(b)(5)
Registration No.: 333-253605
333-253605-1
PROSPECTUS SUPPLEMENT
(To Prospectus dated
May 15, 2023)
Pfizer Investment Enterprises Pte. Ltd.
(UEN 202315648E)
(incorporated as
a private company limited by shares under the laws of the Republic of Singapore)
Guaranteed on a senior unsecured basis by Pfizer
Inc.
$3,000,000,000 4.650% NOTES DUE 2025
$3,000,000,000 4.450% NOTES DUE 2026
$4,000,000,000 4.450% NOTES DUE 2028
$3,000,000,000 4.650% NOTES DUE 2030
$5,000,000,000 4.750% NOTES DUE 2033
$3,000,000,000 5.110% NOTES DUE 2043
$6,000,000,000 5.300% NOTES DUE 2053
$4,000,000,000 5.340% NOTES DUE 2063
The
2025 notes (the 2025 notes) will mature on May 19, 2025, the 2026 notes (the 2026 notes) will mature on May 19, 2026, the 2028 notes (the 2028 notes) will mature on May 19, 2028, the 2030 notes (the 2030
notes) will mature on May 19, 2030, the 2033 notes (the 2033 notes) will mature on May 19, 2033, the 2043 notes (the 2043 notes) will mature on May 19, 2043, the 2053 notes (the 2053 notes) will mature on
May 19, 2053 and the 2063 notes (the 2063 notes) will mature on May 19, 2063. The 2025 notes, the 2026 notes, the 2028 notes, the 2030 notes, the 2033 notes, the 2043 notes, the 2053 notes and the 2063 notes are referred to collectively
as the notes. The notes will be Pfizer Investment Enterprises Pte. Ltd.s (the Issuer) unsecured and unsubordinated debt obligations, will not have the benefit of any sinking fund and will be fully and unconditionally
guaranteed (the note guarantee), on a senior unsecured basis by Pfizer Inc., the Issuers parent company (the Parent). The notes and the note guarantee will rank equally in right of payment with all of the Issuers
and the Parents other unsubordinated indebtedness, respectively, from time to time outstanding. Interest on the notes for each series will be payable semi-annually in arrears on May 19 and November 19 of each year, beginning on November
19, 2023. The notes are redeemable in whole, or in part, at the Issuers option at the redemption prices set forth in this prospectus supplement. In addition, the Issuer may redeem the notes in whole, but not in part, at any time in the event
of certain developments affecting taxation. See Description of NotesOptional Redemption; Redemption for Tax Reasons; No Sinking Fund. The indenture (as defined herein) and the notes will be governed by the laws of the State of New
York.
This offering is part of the financing for our proposed acquisition of Seagen Inc. (Seagen), which is referred to as the
Merger. The Merger has not been completed as of the date of this prospectus supplement. We currently expect the Merger to be completed by late 2023 or early 2024. The completion of the Merger is subject to customary closing conditions
set forth in the Merger Agreement (as defined herein), and we cannot guarantee that the Merger will be completed on a timely basis, on the terms described herein, or at all. This offering is not conditioned upon the completion of the Merger, which,
if completed, will occur subsequent to the closing of this offering. However, if (i) the Merger is not consummated on or before the later of (x) September 19, 2024 and (y) the date that is five business days after any later date
to which Seagen and the Parent may agree to extend the Outside Date in the Merger Agreement (the Special Mandatory Redemption End Date) or (ii) the Issuer notifies the trustee under the indenture that we will not pursue
consummation of the Merger, the Issuer will be required to redeem each series of the notes (the Special Mandatory Redemption), other than the 2033 notes and the 2053 notes, at a special mandatory redemption price equal to 101% of the
aggregate principal amount of such series of notes, plus accrued and unpaid interest, if any, to, but excluding, the Special Mandatory Redemption Date (as defined herein). Upon completion of a Special Mandatory Redemption, the Parent will assume all
obligations of the Issuer under the 2033 notes and the 2053 notes and the Issuer will be released under the indenture governing the 2033 notes and the 2053 notes. The proceeds from this offering will not be deposited into an escrow account pending
completion of the Merger or any Special Mandatory Redemption, nor will the Issuer be required to grant any security interest or other lien on those proceeds to secure any redemption of the notes. See Description of NotesSpecial Mandatory
Redemption.
(continued on the next page)