Viatris Inc美股招股说明书(2026-06-12版)

TABLE OF CONTENTS This preliminary prospectus supplement and the accompanying prospectus relate to an effective registration statementunder the Securities Act of 1933, but the preliminary prospectus supplement is not complete and may be changed. Thispreliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities and we arenot soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted. Filed Pursuant to Rule 424(b)(5)Registration No. 333-287087 SUBJECT TO COMPLETION, DATED JUNE 12, 2026 Preliminary Prospectus Supplement(To Prospectus dated May8, 2025) Viatris Inc.€% Senior Notes due Guaranteed on a senior unsecured basis by Mylan Inc., Mylan II B.V. and Utah Acquisition Sub Inc. We are offering €aggregate principal amount of% Senior Notes due(the “notes”). The notes will bear interest at a rate of% peryear and will mature on. We will pay interest on the notes annually in arrears onof each year, beginning on, 2027. We may redeem the notes in whole or in part at any time at the applicable redemption price set forth in this prospectus supplement under “Description ofNotes — Optional Redemption.” If a Change of Control Repurchase Event, as described in this prospectus supplement under the heading “Description of Notes—Purchase of Notes upon a Change of Control Repurchase Event,” occurs, we must offer to purchase the notes from holders at a purchase price equal to 101% of theprincipal amount thereof, plus accrued and unpaid interest thereon, if any, to, but excluding, the repurchase date, unless we have exercised our right to redeem thenotes. The notes will be senior unsecured obligations of the Issuer and will be (i)pari passuin right of payment with all existing and future senior indebtedness ofthe Issuer, (ii) senior in right of payment to all future indebtedness of the Issuer that is expressly subordinated to the notes, (iii) effectively subordinated to all futuresecured indebtedness of the Issuer to the extent of the value of the collateral securing such indebtedness and (iv) effectively subordinated to all existing and futureindebtedness and other liabilities, including trade payables, of the existing and future subsidiaries of the Issuer that do not guarantee the notes. The notes will initially be fully and unconditionally guaranteed on a senior unsecured basis by Mylan Inc., Mylan II B.V. and Utah Acquisition Sub Inc. Theguarantee of each guarantor will be senior unsecured obligations of such guarantor and will be (i)pari passuin right of payment with existing and future seniorobligations of such guarantor, (ii) senior in right of payment to all future indebtedness of such guarantor that is expressly subordinated to such guarantee, (iii)effectively subordinated to all future secured indebtedness of such guarantor to the extent of the value of the collateral securing such indebtedness and(iv)effectively subordinated to all existing and future indebtedness and other liabilities, including trade payables, of the existing and future subsidiaries of suchguarantor that do not guarantee the notes. We intend to use the net proceeds from this offering to (i) fund the repayment of any amounts borrowed under the Revolving Credit Facility (as definedherein) in June2026 in connection with the repayment of the 2026 Senior Notes (as defined herein) and (ii) the remainder, if any, to replenish cash that will beutilized in connection with the repayment of the 2026 Senior Notes, with such cash to be used for general corporate purposes. For a more detailed discussion, see“Summary—Recent Developments—Repayment of 2026 Senior Notes” and “Use of Proceeds.” Investing in the notes involves risks. You should carefully consider the information referred to under the heading “Risk Factors” beginning on pageS-7of this prospectus supplement and under similar headings in the documents that are incorporated by reference herein for a discussion of certain risksyou should consider prior to deciding whether to purchase the notes. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of the securities or determinedthat this prospectus supplement or the accompanying prospectus is accurate or complete. Any representation to the contrary is a criminal offense. PublicOffering PriceUnderwritingDiscountProceeds toViatris (BeforeExpenses)Per note%%%Total€€€ The public offering price and proceeds to Viatris (before expenses) set forth above do not include accrued interest, if any. Interest on the notes will accrue, 2026 and accrued interest must be paid by the purchaser if the notes are delivered after that date. The notes are a new issue of securities with no established trading market. Application has been made to the Irish Stock Exchange plc trading as EuronextDublin (“Euronext Dublin”) for the approval of this document as listing particulars. Application has also been made to Euronext