ACQUISITIONS, COLLABORATIONS AND OTHER ARRANGEMENTS	3 Months Ended
ACQUISITIONS, COLLABORATIONS AND OTHER ARRANGEMENTS	Mar. 31, 2025
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
ACQUISITIONS, COLLABORATIONS AND OTHER ARRANGEMENTS	ACQUISITIONS, COLLABORATIONS AND OTHER ARRANGEMENTS We enter into acquisitions, licensing and strategic collaborations and other similar arrangements with third parties for the research, development and commercialization of certain products and product candidates. The collaborations involve two or more parties who are active participants in the operating activities of the collaboration and are exposed to significant risks and rewards depending on the commercial success of the activities. The financial terms of these arrangements may include non-refundable upfront payments, expense reimbursements, payments by us for options to acquire certain rights, contingent obligations by us for potential development and regulatory milestone payments and/or sales-based milestone payments, royalty payments, revenue or profit-sharing arrangements, cost-sharing arrangements and equity investments. Acquisitions CymaBay In March 2024, we completed the acquisition of CymaBay Therapeutics, Inc. (“CymaBay”) for total consideration of $3.9 billion, net of cash acquired. Upon closing, CymaBay became our wholly-owned subsidiary. We accounted for this transaction as an asset acquisition since the lead asset, seladelpar, an investigational, oral, peroxisome proliferator-activated receptor delta agonist shown to regulate critical metabolic and liver disease pathways, represented substantially all of the fair value of the gross assets acquired. During the three months ended March 31, 2024, we recorded a $3.9 billion charge, representing an acquired IPR&D asset with no alternative future use, to Acquired in-process research and development expenses, as well as share-based compensation expense of $133 million related to the cash settlement of unvested CymaBay employee stock awards attributable to post-acquisition services, with $67 million being recorded in Research and development expenses and $67 million in Selling, general and administrative expenses on our Condensed Consolidated Statements of Operations. Collaborations and Other Arrangements Galapagos In January 2025, we agreed to amend our option, license and collaboration agreement with Galapagos (the “OLCA”) commensurate with Galapagos’ announcement for a planned separation of Galapagos into two entities: a newly to be formed company (to be named at a later date, herein “SpinCo”) with an initial capital allocation of up to approximately €2.45 billion (approximately $2.54 billion as of the time of announcement) and Galapagos. At the time of separation, should it occur, Galapagos’ and our rights and responsibilities under the OLCA would transfer to SpinCo, and Galapagos would gain full global development and commercialization rights to its pipeline, subject to payment of single digit royalties to Gilead on net sales of certain products. This separation is expected to occur by mid-2025. As a result of the amendment, Gilead’s ownership stake in Galapagos is subject to lock-up until December 2025, and upon separation, Gilead will hold approximately 25% of the outstanding shares in both Galapagos and SpinCo and will be subject to a lock-up of Galapagos shares through March 2027 and of SpinCo shares until six months after the separation, subject to certain customary exceptions and early termination provisions. The two Gilead designees appointed to Galapagos’ board of directors will step down upon the separation and Gilead will be entitled to nominate two directors to SpinCo’s board. LEO Pharma In January 2025, we entered into a strategic partnership with LEO Pharma A/S (“LEO Pharma”) to accelerate the development and commercialization of LEO Pharma’s small molecule oral signal transducer and activator of transcription 6 (“STAT6”) programs for the potential treatment of patients with inflammatory diseases. Gilead will have global rights to develop, manufacture, and commercialize the small molecule oral STAT6 program. LEO Pharma will have the option to potentially co-commercialize oral programs for dermatology outside the U.S. LEO Pharma will hold exclusive global rights to STAT6 topical formulations in dermatology. Upon closing of the agreement, we made a $250 million upfront payment to LEO Pharma which was charged to Acquired in-process research and development expenses on our Condensed Consolidated Statements of Operations. In addition, LEO Pharma is eligible to receive up to approximately $1.5 billion in additional milestone payments and may also receive tiered royalties on sales of oral STAT6 products. Arcus In January 2024, we amended our collaboration agreement with Arcus whereby we acquired approximately 15.2 million additional shares of Arcus common stock at a premium for $320 million. We recorded $233 million for the fair value of the equity investment in Prepaid and other current assets on our Condensed Consolidated Balance Sheets and $87 million for the premium in Other (income) expense, net on our Condensed Consolidated Statements of Operations. As part of the January 2024 amendment, we committed to a $100 million continuation fee, which was charged to Acquired in-process research and development expenses on our Condensed Consolidated Statements of Operations and paid later in 2024. Our number of designees on Arcus’ board of directors was also increased to three. As of March 31, 2025, we held 31.4 million shares, or approximately 30% of the issued and outstanding voting stock of Arcus.