GSK : Supplementary Prospectus

SUPPLEMENT DATED 3rd NOVEMBER, 2022 TO

THE PROSPECTUS DATED 7th SEPTEMBER, 2022

G S K p l c

(incorporated in England and Wales with limited liability under registered number 3888792)

GlaxoSmithKline Capital plc

(incorporated in England and Wales with limited liability under registered number 2258699)

GSK Capital K.K.

(incorporated with limited liability in Japan under registered number 0110-01-117664)

GSK Capital B.V.

(incorporated with limited liability in the Netherlands under registered number 81761198)

£20,000,000,000

Euro Medium Term Note Programme

unconditionally and irrevocably guaranteed in the case of Notes issued by GlaxoSmithKline Capital plc, GSK Capital K.K. and GSK Capital B.V. by GSK plc

(incorporated in England and Wales with limited liability under registered number 3888792)

This supplement (the "Supplement", which definition shall also include all information incorporated by reference herein) to the base prospectus dated 7th September, 2022 (the "Prospectus", which definition includes all information incorporated by reference therein) constitutes a supplementary prospectus for the purposes of Article 23 of Regulation (EU) 2017/1129 as it forms part of domestic law of the United Kingdom by virtue of the European Union (Withdrawal) Act 2018 (the "UK Prospectus Regulation") and is prepared in connection with the £20,000,000,000 Euro Medium Term Note Programme (the "Programme") of GSK plc, GlaxoSmithKline Capital plc ("GSK Capital plc"), GSK Capital K.K. ("GSK Capital K.K.") and GSK Capital B.V. ("GSK Capital B.V." and, together with GSK plc, GSK Capital plc and GSK Capital K.K., the "Issuers" and each an "Issuer"). The payment of all amounts owing in respect of Notes issued under the Programme by GSK Capital plc, GSK Capital K.K. and GSK Capital B.V. will be unconditionally and irrevocably guaranteed by GSK plc (the "Guarantor").

Terms defined in the Prospectus have the same meaning when used in this Supplement.

This Supplement has been approved by the United Kingdom's Financial Conduct Authority (the "FCA"), in its capacity as competent authority for the purposes of the UK Prospectus Regulation, as a supplement to the Prospectus. This Supplement together with the Prospectus comprises a base prospectus for the purposes of Article 8 of the UK Prospectus Regulation.

Each Issuer and the Guarantor accepts responsibility for the information contained in this Supplement. To the best of the knowledge and belief of each Issuer and the Guarantor the information contained in this Supplement is in accordance with the facts and this Supplement does not omit anything likely to affect the import of such information. No other person has authorised or is responsible for the whole or any part of this Supplement or has any liability with respect to it.

This Supplement is supplemental to, updates, must be read in conjunction with, and forms part of, the Prospectus and any other supplements to the Prospectus issued by the Issuers and the Guarantor.

Other than in relation to the documents which are deemed to be incorporated by reference, the information on the websites to which this Supplement refers does not form part of this Supplement and has not been scrutinised or approved by the FCA.

The purpose of this Supplement is to (i) incorporate by reference into the Prospectus the Group's Results Announcement for the third quarter 2022 (as defined below) and (ii) incorporate by reference the Group's press release dated 26th September, 2022 announcing Iain Mackay's retirement as Chief Financial Officer of GSK plc.

Documents Incorporated by Reference

The following documents which have been previously published, or are published simultaneously with this Supplement and have been filed with the FCA shall be deemed to be incorporated in, and to form part of, this Supplement and, by virtue of this Supplement, shall be deemed to be incorporated in, and to form part of, the Prospectus:

1. the press release dated 2nd November, 2022 (which can be accessed from the following hyperlink: https://www.gsk.com/media/9632/q3-2022-results-announcement.pdf) containing the unaudited interim condensed financial information of the Group for the three months ended 30th September, 2022 (the "Group's Results Announcement for the third quarter 2022"); and
2. the press release dated 26th September, 2022 (which can be accessed from the following hyperlink https://www.gsk.com/en-gb/media/press-releases/iain-mackay-chief-financial-officer-to-retire-from-gsk-julie-brown-appointed-as-successor/)announcing that Iain Mackay has decided to retire from GSK and that the Board has agreed that he will step down as Chief Financial Officer, and as an Executive Director of the Board in May 2023, and also announcing that Julie Brown will be appointed as his

successor;

(together the "Press Releases").

Any documents themselves incorporated by reference in the Press Releases shall not form part of this Supplement.

Copies of this Supplement and the Press Releases, incorporated by reference herein have been filed with Morningstar plc (appointed by the FCA to act as the National Storage Mechanism), and are available for viewing at https://data.fca.org.uk/#/nsm/nationalstoragemechanism.

Additional Information

The first two paragraphs under the subheading "Significant or Material Change" on page 105 of the Prospectus shall be deemed to be deleted in their entirety and replaced with the following text:

"There has been no significant change in the financial performance of GSK plc and/or the Group since 30th September, 2022.

There has been no significant change in the financial position of GSK plc and/or the Group since 30th September, 2022 and there has been no material adverse change in the prospects of GSK plc and/or the Group since 31st December, 2021."

The second paragraph under the subheading "Litigation" on page 105 of the Prospectus shall be deemed to be deleted in its entirety and replaced with the following text:

"Save as disclosed in Note 14, "Taxation", to the Financial Statements set out on pages 189 to 191 of the Group's Annual Report 2021, Note 46, "Legal proceedings", to the Financial Statements set out on pages 248 to 250 of the Group's Annual Report 2021, "Legal matters" and "Zantac" each set out on page 50 and "Taxation" set out on pages 16 and 28 of the Group's Results Announcement for the third quarter 2022, there are no governmental, legal or arbitration proceedings, including any which are pending or threatened, of which the Issuers or the Guarantor are aware, which may have, or have had during the 12 months prior to the date of this Prospectus or in the recent past, a significant effect on the financial position or profitability of any of GSK plc and/or GSK Capital plc and/or GSK Capital K.K. and/or GSK Capital B.V. and/or the Group."

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To the extent there is any inconsistency between (a) any statement in this Supplement or any statement incorporated by reference into the Prospectus by this Supplement and (b) any other statement in, or incorporated by reference in, the Prospectus prior to the date of this Supplement, the statements in (a) above will prevail.

Save as disclosed in this Supplement and the Prospectus, neither the Issuers nor the Guarantor is aware of any other significant new factor, material mistake or material inaccuracy relating to information included in the Prospectus which is capable of affecting an informed assessment by investors of Notes issued under the Programme since the publication of the Prospectus.

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