GSK plc (LSE/NYSE: GSK) (“GSK”), and Shionogi & Co., Ltd (Head Office: Osaka, Japan; Chief Executive Officer: Isao Teshirogi, Ph.D) (“Shionogi”) today announced that they have reached agreement together with Pfizer Inc. (NYSE: PFE) (“Pfizer”) for the 11.7% economic interest in ViiV Healthcare Limited (“ViiV Healthcare”) currently held by Pfizer to be replaced with an investment by Shionogi. As a result of this transaction, Shionogi will increase its economic interest in ViiV Healthcare to 21.7%. GSK will maintain its 78.3% majority owned economic interest. Shionogi will continue to have one Director position on the ViiV Healthcare Board, and will be represented by Dr John Keller who has been a Director of ViiV Healthcare since 2012.

Under the terms of the agreement, ViiV Healthcare will issue new shares to Shionogi for consideration of $2.125 bn and cancel Pfizer’s holding in ViiV Healthcare. Pfizer will receive $1.875 bn and GSK will receive a special dividend of $0.250 bn (payable in GBP).

ViiV Healthcare, the global specialist HIV company, is dedicated to delivering advances in treatment and care for people living with HIV and for people who could benefit from HIV prevention. .

David Redfern, Chair of ViiV Healthcare said: “This agreement simplifies ViiV’s shareholder structure and we look forward to continuing our highly successful collaboration with Shionogi to advance ViiV’s pipeline and portfolio of long-acting injectable HIV treatment and prevention medicines. GSK would also like to thank Pfizer for its longstanding partnership in the development of ViiV since its establishment in 2009.”

John Keller, Ph.D., Director of the Board, Senior Vice President, R&D Supervisory Unit at Shionogi said: “Shionogi is dedicated to addressing major infectious diseases, with HIV being one of our most important focus areas, as reflected by our role in the discovery of the innovative integrase inhibitors dolutegravir and cabotegravir. Our ongoing HIV research continues to contribute to ViiV’s pipeline through licensing agreements, as is the case for the third-generation integrase inhibitor S-395598/VH 4524184. We are delighted to further deepen our strategic partnership with GSK and ViiV through this agreement, redoubling our commitment and participation in improving the lives of people living with or affected by HIV.”

Financial and Regulatory Considerations

Completion of the transaction is subject to certain regulatory clearances in relevant markets, and is expected to occur during the first quarter of 2026.

On completion, GSK will extinguish the Pfizer put option liability through retained earnings. The liability will be remeasured immediately prior to completion, on the same methodology as at 31 December 2025, with any fair value change in the liability recognised as an adjusting item through other operating income.