COLLABORATIONS AND OTHER ARRANGEMENTS	12 Months Ended
Dec. 31, 2023
Collaborative and Other Arrangements [Abstract]
COLLABORATIONS AND OTHER ARRANGEMENTS	COLLABORATIONS AND OTHER ARRANGEMENTS We enter into licensing and strategic collaborations and other similar arrangements with third parties for the research, development and commercialization of certain products and product candidates. These arrangements may 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 or 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. Development milestone payments are recorded in our Consolidated Statements of Income as incurred, which is generally when the corresponding events become probable. Regulatory milestone payments are capitalized as intangible assets and amortized to Cost of goods sold over the term of the respective collaboration arrangement. Certain payments are contingent upon the occurrence of various future events that have a high degree of uncertainty. Arcellx In January 2023, we closed an agreement to enter into a global strategic collaboration with Arcellx, a public company, to co-develop and co-commercialize Arcellx’s lead late-stage product candidate, CART-ddBCMA, for the treatment of patients with relapsed or refractory multiple myeloma, and potential future next-generation autologous and non-autologous products. In December 2023, we expanded the scope of the collaboration to include lymphomas and exercised our option to negotiate a license for Arcellx’s ARC-SparX program, ACLX-001, in multiple myeloma. In conjunction with these collaboration agreements, we recorded a combined $313 million charge to Acquired in-process research and development expenses on our Consolidated Statements of Income in 2023, primarily related to upfront payments, as well as a combined equity investment of $299 million. Our equity investment is subject to lock-up provisions until June 2025 and is included in Other long-term assets on our Consolidated Balance Sheets as of December 31, 2023. The companies will share development, clinical trial and commercialization costs for CART-ddBCMA and will jointly commercialize the product and split U.S. profits 50/50. Outside the U.S., we will commercialize the product and Arcellx will receive royalties on sales. Arcellx is eligible to receive performance-based development and regulatory milestone payments of up to $1.5 billion related to CART-ddBCMA, a potential future next-generation autologous product and a potential future non-autologous product, with further commercial milestone payments, profit split payments on co-promoted products and royalties on at least a portion of worldwide net sales, depending on whether Arcellx opts in to co-promote the future products. If additional future products are developed, Arcellx would be eligible to receive additional milestone payments, profit split payments on co-promoted products and royalties on at least a portion of worldwide net sales, depending on whether Arcellx opts in to co-promote these additional future products as well. Dragonfly In April 2022, we entered into a strategic research collaboration agreement (the “Dragonfly Collaboration Agreement”) with Dragonfly Therapeutics, Inc. (“Dragonfly”) to develop natural killer (“NK”) cell engager-based immunotherapies for oncology and inflammation indications. Under the terms of the Dragonfly Collaboration Agreement, we received an exclusive, worldwide license from Dragonfly for the 5T4-targeting investigational immunotherapy program, DF7001, as well as options, after the completion of certain preclinical activities, to license exclusive, worldwide rights to develop and commercialize additional NK cell engager programs using the Dragonfly Tri-specific NK Engager platform. Upon the closing of the Dragonfly Collaboration Agreement, we made a $300 million upfront payment to Dragonfly, and we made an additional $15 million payment related to a target selection in connection with an August 2022 amendment to the agreement, which were recorded in Acquired in-process research and development expenses on our Consolidated Statements of Income during the year ended December 31, 2022. In July 2023, we mutually agreed to terminate the DF7001 program. If we exercise our options on additional NK cell engager programs, Dragonfly would be eligible to receive opt-in payments and performance-based development, regulatory and commercial milestone payments and royalties on worldwide net sales on these optioned programs. Merck On March 13, 2021, we entered into a license and collaboration agreement with Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc. (“Merck”) to jointly develop and commercialize long-acting investigational treatments in HIV that combine Gilead’s investigational capsid inhibitor, lenacapavir, and Merck’s investigational nucleoside reverse transcriptase translocation inhibitor, islatravir, with other formulations potentially added to the collaboration as mutually agreed. The collaboration is initially focused on long-acting oral and injectable formulations. Under the terms of the agreement, as amended, Gilead and Merck will mostly share global development and commercialization costs at 60% and 40%, respectively, across the oral and injectable formulation programs. For long-acting oral products, if approved, Gilead would lead commercialization in the U.S., and Merck would lead commercialization in the European Union (“EU”) and rest of the world. For long-acting injectable products, if approved, Merck would lead commercialization in the U.S. and Gilead would lead commercialization in the EU and rest of the world. Under the terms of the agreement, Gilead and Merck would jointly promote the combination products in the U.S. and certain other major markets. If successful, we would share global product revenues with Merck equally until product revenues surpass certain pre-determined per formulation revenue tiers. Upon passing $2.0 billion in net product sales for the oral combination in a given calendar year, our share of revenue would increase to 65% for any revenues above the threshold for such calendar year. Upon passing $3.5 billion in net product sales for the injectable combination in a given calendar year, our share of revenue will increase to 65% for any revenues above the threshold for such calendar year. Reimbursements of R&D costs to or from Merck are recorded within Research and development expenses on our Consolidated Statements of Income. Expenses recognized under the agreement were not material for the years ended December 31, 2023, 2022 and 2021. No revenues have been recognized under the agreement for the years ended December 31, 2023, 2022 and 2021. We will also have the option to license certain of Merck’s investigational oral integrase inhibitors to develop in combination with lenacapavir. Reciprocally, Merck will have the option to license certain of Gilead’s investigational oral integrase inhibitors to develop in combination with islatravir. Each company may exercise its option for such investigational oral integrase inhibitor of the other company within the first five years after execution of the agreement, following completion of the first Phase 1 clinical trial of that integrase inhibitor. Upon exercise of an option, the companies will split development costs and revenues, unless the non-exercising company decides to opt out, in which case the non-exercising company will be paid a royalty. Arcus On May 27, 2020, we entered into a transaction with Arcus, a publicly traded oncology-focused biopharmaceutical company, which included entry into an option, license and collaboration agreement (the “Collaboration Agreement”), with Gilead having the right to opt in to all current and future clinical-stage product candidates for up to ten years following the closing of the transaction, and a common stock purchase agreement and an investor rights agreement (together, and as subsequently amended the “Stock Purchase Agreements”). In November 2021, we exercised our options to three of Arcus’ clinical stage programs and amended the Collaboration Agreement. The option exercise and amendment transaction closed in December 2021, triggering collaboration opt-in payments of $725 million and waiving the $100 million option continuation payment which would have been due to Arcus in the third quarter of 2022. The net option charge of $625 million was included within Acquired in-process research and development expenses on our Consolidated Statements of Income for the year ended December 31, 2021. The collaboration opt-in payments of $725 million were recorded in Other current liabilities on our Consolidated Balance Sheets as of December 31, 2021 and paid to Arcus in January 2022. Our payments to Arcus were included within Net cash used in investing activities on our Consolidated Statements of Cash Flows in the first quarter of 2022. In May 2023, we again amended the Collaboration Agreement to initiate research programs against up to four targets jointly selected by the parties that are applicable to inflammatory diseases. As part of the amendment, we paid a $35 million upfront fee, which was charged to Acquired in-process research and development expenses on our Consolidated Statements of Income. Gilead may exercise an option to license each program at two separate, prespecified time points. If Gilead exercises its option at the earlier time point for the first two target programs, Arcus would be eligible to receive up to $420 million in future option and milestone payments and tiered royalties for each optioned program. For any other option exercise by Gilead for the four target programs, the parties would have rights to co-develop and share global development costs and to co-commercialize and share profits in the U.S. for optioned programs. Under the amended Collaboration Agreement, the companies co-develop and share the global costs related to these clinical programs. We recorded $189 million and $187 million of such costs in Research and development expenses on our Consolidated Statements of Income for the years ended December 31, 2023 and 2022, respectively. If the optioned molecules achieve regulatory approval, the companies will co-commercialize and equally share profits in the U.S. Gilead will hold exclusive commercialization rights outside the U.S., subject to any rights of Arcus’s existing collaboration partners, and will pay to Arcus tiered royalties as a percentage of net sales ranging from the mid teens to low twenties. Under the amended Collaboration Agreement, we may also pay an additional $100 million at our option on each of the fourth, sixth and eighth anniversaries of the agreement, unless terminated early, to maintain the rights to opt in to future Arcus programs for the duration of the contact term. Under the Stock Purchase Agreements, we have the right to purchase from Arcus additional shares up to a maximum of 35% of the outstanding voting stock of Arcus over a five-year period ending in the third quarter of 2025. We were also subject to a three-year standstill, restricting certain other activity on our part, which expired in the second quarter of 2023. We have made various purchases of shares since the original closing of the agreement and, following our latest purchase in the second quarter of 2023, we owned a total of 14.8 million shares, which represented approximately 19.9% of the issued and outstanding voting stock of Arcus at that time. As of December 31, 2023, we had two designees on Arcus’ board of directors. In January 2024, we announced an amendment to the Collaboration Agreement with Arcus and made an additional equity investment in Arcus for $320 million, increasing our ownership to 33%. Under the amended Collaboration Agreement, we agreed to pay the $100 million fourth anniversary option continuation fee in 2024. We also increased our number of designees on Arcus’ board of directors to three. Pionyr In June 2020, we entered into a transaction with Pionyr Immuotherapeutics (“Pionyr”), a privately held company pursuing novel biology in the field of immuno-oncology, which included entry into two separate agreements, one related to the initial acquisition of a 49.9% equity interest in Pionyr, and the other providing us the exclusive option, subject to certain terms and conditions, to acquire the remaining outstanding capital stock of Pionyr (the “Pionyr Merger and Option Agreements”) and a R&D service agreement. In March 2023, we terminated the R&D service agreement, waived our exclusive option to acquire Pionyr and certain other rights under the Pionyr Merger and Option Agreements and recorded a $70 million charge to Other income (expense), net on our Consolidated Statements of Income, writing off the full value of the option that had previously been recorded in Other long-term assets on our Consolidated Balance Sheets. We previously accounted for our investment in Pionyr using the equity method of accounting because our equity interest provided us with the ability to exercise significant influence over Pionyr. The carrying value of our equity method investment in Pionyr was zero as of December 31, 2022. In August 2023, Pionyr was acquired by Ikena Oncology, Inc. (“Ikena”), a publicly traded company, and our equity interest was converted to shares of Ikena stock. Tizona In July 2020, we entered into a transaction with Tizona Therapeutics, Inc. (“Tizona”), a privately held company developing cancer immunotherapies, which included entry into two separate agreements, one related to the initial acquisition of a 49.9% equity interest in Tizona, and the other providing us the exclusive option, subject to certain terms and conditions, to acquire the remaining outstanding capital stock of Tizona (the “Tizona Merger and Option Agreements”) and a development agreement. In September 2023, we terminated the development agreement, waived our exclusive option to acquire Tizona and certain other rights under the Tizona Merger and Option Agreements and recorded a $41 million charge to Other income (expense), net on our Consolidated Statements of Income, writing off the full value of the option that had previously been recorded in Other long-term assets on our Consolidated Balance Sheets. We account for our investment in Tizona using the equity method of accounting because our equity interest provides us with the ability to exercise significant influence over Tizona. The carrying value of our equity method investment in Tizona was zero as of December 31, 2023 and 2022. Galapagos Filgotinib Collaboration In October 2023, we amended a previous agreement with Galapagos, a clinical-stage biotechnology company based in Belgium, related to the development and commercialization of filgotinib, a JAK1-selective inhibitor being evaluated for inflammatory disease indications, to terminate the global development cost-sharing arrangement and Galapagos’ obligation to pay tiered royalties to us on net sales in Europe. As a result, we wrote off the remaining $51 million balance of our related finite-lived intangible asset as discussed in Note 9. Goodwill and Intangible Assets. We had also previously paid Galapagos €160 million (or approximately $190 million) related to an agreement to terminate Galapagos’ right to receive any future milestone payments relating to filgotinib in Europe, with the full amount being expensed in 2020 and €110 million (or approximately $130 million) paid in 2021 and €50 million (or approximately $60 million) paid in 2022. Global Collaboration In August 2019, we closed an option, license and collaboration agreement (the “Galapagos Collaboration Agreement”) and a subscription agreement (the “Galapagos Subscription Agreement”), each with Galapagos, pursuant to which the parties entered into a global collaboration that covers Galapagos’ current and future product portfolio (other than filgotinib). Pursuant to the Galapagos Subscription Agreement, we purchased 6.8 million new ordinary shares of Galapagos and were issued warrants that confer the right to subscribe, from time to time, for a number of new shares to be issued by Galapagos sufficient to bring the number of shares owned by us to 29.9% of the issued and outstanding shares at the time of our exercises. We currently own 16.7 million shares or approximately 25.8% of the shares issued and outstanding at the time of last purchase in 2019. We are subject to a 10-year standstill restricting our ability to acquire voting securities of Galapagos exceeding more than 29.9% of the then-issued and outstanding voting securities of Galapagos. We agreed not to, without the prior consent of Galapagos, dispose of any equity securities of Galapagos prior to the second anniversary of the closing of the Galapagos Subscription Agreement or dispose of any equity securities of Galapagos thereafter until the fifth anniversary of the closing of the Galapagos Subscription Agreement, if after such disposal we would own less than 20.1% of the then-issued and outstanding voting securities of Galapagos, subject to certain exceptions and termination events. In April 2021, we amended the Galapagos Subscription Agreement to extend the initial lock-up provision for certain Galapagos shares from August 2021 to August 2024. With respect to programs in Galapagos’ current and future pipeline, if we exercise our option to a program, we will pay a $150 million option exercise fee per program. In addition, Galapagos will receive tiered royalties ranging from 20% to 24% on net sales in our territories of each Galapagos product optioned by us. If we exercise our option for a program, the parties will share equally in development costs and mutually agreed commercialization costs incurred subsequent to our exercise of the option. We may terminate the collaboration in its entirety or on a program-by-program and country-by-country basis with advance notice as well as following other customary termination events. We have two designees appointed to Galapagos’ board of directors. Janssen Complera/Eviplera and Odefsey In 2009, we entered into a license and collaboration agreement with Janssen to develop and commercialize a fixed-dose combination of our Truvada and Janssen’s non-nucleoside reverse transcriptase inhibitor, rilpivirine. This combination was approved in the U.S. and EU in 2011, and is sold under the brand name Complera in the U.S. and Eviplera in the EU. The agreement was amended in 2014 to expand the collaboration to include another product containing Janssen’s rilpivirine and our emtricitabine and tenofovir alafenamide (“Odefsey”). Under the amended agreement, Janssen granted us an exclusive license to Complera/Eviplera and Odefsey worldwide, but retained rights to distribute both combination products in certain countries outside of the U.S. Neither party is restricted from combining its drugs with any other drug products except those which are similar to the components of Complera/Eviplera and Odefsey. We are responsible for manufacturing Complera/Eviplera and Odefsey and have the lead role in registration, distribution and commercialization of both products except in the countries where Janssen distributes. Janssen has exercised a right to co-detail the combination product in some of the countries where we are the selling party. Under the financial provisions of the 2014 amendment, the selling party sets the price of the combined products and the parties share revenues based on the ratio of the net selling prices of the party’s component(s), subject to certain restrictions and adjustments. We retain a specified percentage of Janssen’s share of revenues, including up to 30% in major markets. Sales of these products are included in Product sales and Janssen’s share of revenues is included in Cost of goods sold on our Consolidated Statements of Income. Cost of goods sold relating to Janssen’s share was $430 million, $483 million and $530 million for the years ended December 31, 2023, 2022 and 2021, respectively. Termination of the agreement may be on a product or country basis and will depend on the circumstances, including withdrawal of a product from the market, material breach by either party or expiry of the revenue share payment term. We may terminate the agreement without cause with respect to the countries where we sell the products, in which case Janssen has the right to become the selling party for such country if the product has launched but has been on the market for fewer than 10 years. Symtuza In 2014, we amended a license and collaboration agreement with Janssen to develop and commercialize a fixed-dose combination of Janssen’s darunavir and our cobicistat, emtricitabine and tenofovir alafenamide (“Gilead Compounds”). This combination was approved in the U.S. and EU in July 2018 and September 2017, respectively, and is sold under the brand name Symtuza. Under the terms of the 2014 amendment, we granted Janssen an exclusive license to Symtuza worldwide. Janssen is responsible for manufacturing, registration, distribution and commercialization of Symtuza worldwide. We are responsible for the intellectual property related to the Gilead Compounds and are the exclusive supplier of the Gilead Compounds. Neither party is restricted from combining its drugs with any other drug products except those which are similar to the components of Symtuza. Janssen sets the price of Symtuza and the parties share revenue based on the ratio of the net selling prices of the party’s component(s), subject to certain restrictions and adjustments. The intellectual property license and supply obligations related to the Gilead Compounds are accounted for as a single performance obligation. As the license was deemed to be the predominant item to which the revenue share relates, we recognize our share of the Symtuza revenue in the period when the corresponding sales of Symtuza by Janssen occur. We record our share of the Symtuza revenue as Product sales on our Consolidated Statements of Income primarily because we supply the Gilead Compounds to Janssen for Symtuza. Termination of the agreement may be on a product or country basis and will depend on the circumstances, including withdrawal of a product from the market, material breach by either party or expiry of the revenue share payment term. Janssen may terminate the agreement without cause on a country-by-country basis, in which case Gilead has the right to become the selling party for such country(ies) if the product has launched but has been on the market for fewer than 10 years. Janssen may also terminate the entire agreement without cause. Japan Tobacco In 2005, Japan Tobacco, Inc. (“Japan Tobacco”) granted us exclusive rights to develop and commercialize elvitegravir, a novel HIV integrase inhibitor, in all countries of the world, excluding Japan, where Japan Tobacco retained such rights. Effective December 2018, we entered into an agreement with Japan Tobacco to acquire the rights to market and distribute certain products in our HIV portfolio in Japan and to expand our rights to develop and commercialize elvitegravir to include Japan. We are responsible for the marketing of the products as of January 1, 2019. We are responsible for seeking regulatory approval in our territories and are required to use diligent efforts to commercialize elvitegravir for the treatment of HIV infection. We bear all costs and expenses associated with such commercialization efforts and pay a royalty to Japan Tobacco based on our product sales. Our sales of these products are included in Product sales on our Consolidated Statements of Income. Royalties due to Japan Tobacco are included in Cost of goods sold on our Consolidated Statements of Income. Royalty expenses recognized were $167 million, $198 million and $250 million for the years ended December 31, 2023, 2022 and 2021, respectively. Under the terms of the 2018 agreement, we paid Japan Tobacco $559 million in cash and recognized an intangible asset of $550 million reflecting the estimated fair value of the marketing-related rights acquired from Japan Tobacco. The intangible asset is being amortized over nine years, representing the period over which the majority of the benefits are expected to be derived from the applicable products in our HIV portfolio. The amortization expense is classified as selling expense and recorded as Selling, general and administrative expenses on our Consolidated Statements of Income. Termination of the agreement may be on a product or country basis and will depend on the circumstances, including material breach by either party or expiry of royalty payment term. We may also terminate the entire agreement without cause. Everest In April 2019, Everest Medicines (“Everest”) and Immunomedics entered into an agreement granting Everest an exclusive license to develop and commercialize Trodelvy in Greater China, South Korea, Singapore, Indonesia, Philippines, Vietnam, Thailand, Malaysia and Mongolia (the “Territories”). Gilead subsequently acquired Immunomedics in October 2020 and assumed the Everest license and supply agreement, which provided for certain sales milestones and royalties payments to be made to Gilead and was recorded as a $175 million finite-lived asset as part of the purchase accounting. In the fourth quarter of 2022, we reacquired all development and commercialization rights for Trodelvy from Everest and terminated the previous agreement. Under the terms of the new agreement, Gilead made $280 million in upfront termination payments to Everest, of which $84 million was made in 2022 and $196 million was made in 2023. In addition, Everest is eligible to receive up to $175 million in potential additional payments upon achievement of certain regulatory and commercial milestones. We accounted for the new agreement as a contract termination, which includes the reacquisition of commercial rights and the settlement of our pre-existing relationship with Everest. As a result, we recorded an expense of $406 million in Selling, general and administrative expenses on our Consolidated Statements of Income during the year ended December 31, 2022, which primarily represents the upfront costs and write-off of the remaining value of the pre-existing asset related to the prior agreement. Simultaneously, we recorded an acquired finite-lived asset with a fair value of $50 million for the commercial rights reacquired for products approved in the Territories. Abingworth In December 2023, we entered into an arrangement with funds managed by Abingworth LLP (“Abingworth”) under which we will receive up to $210 million to co-fund our development costs for Trodelvy for non-small cell lung cancer in 2023 through 2026. As there is substantive transfer of risk to the financial partner, the development funding is recognized by us as an obligation to perform contractual services. In 2023, we received $50 million from Abingworth. We are recognizing the funding as a reduction of Research and development expenses using an attribution model over the period of the related expenses. If successful, upon regulatory approval in the U.S. for the specified indication, Abingworth will be eligible to receive an approval-based fixed milestone payment of up to $84 million and royalties based on the applicable net sales.

We enter into licensing and strategic collaborations and other similar arrangements with third parties for the research, development and commercialization of certain products and product candidates. These arrangements may 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 or 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. Development milestone payments are recorded in our Consolidated Statements of Income as incurred, which is generally when the corresponding events become probable. Regulatory milestone payments are capitalized as intangible assets and amortized to Cost of goods sold over the term of the respective collaboration arrangement. Certain payments are contingent upon the occurrence of various future events that have a high degree of uncertainty.

In January 2023, we closed an agreement to enter into a global strategic collaboration with Arcellx, a public company, to co-develop and co-commercialize Arcellx’s lead late-stage product candidate, CART-ddBCMA, for the treatment of patients with relapsed or refractory multiple myeloma, and potential future next-generation autologous and non-autologous products. In December 2023, we expanded the scope of the collaboration to include lymphomas and exercised our option to negotiate a license for Arcellx’s ARC-SparX program, ACLX-001, in multiple myeloma. In conjunction with these collaboration agreements, we recorded a combined $313 million charge to Acquired in-process research and development expenses on our Consolidated Statements of Income in 2023, primarily related to upfront payments, as well as a combined equity investment of $299 million. Our equity investment is subject to lock-up provisions until June 2025 and is included in Other long-term assets on our Consolidated Balance Sheets as of December 31, 2023. The companies will share development, clinical trial and commercialization costs for CART-ddBCMA and will jointly commercialize the product and split U.S. profits 50/50. Outside the U.S., we will commercialize the product and Arcellx will receive royalties on sales. Arcellx is eligible to receive performance-based development and regulatory milestone payments of up to $1.5 billion related to CART-ddBCMA, a potential future next-generation autologous product and a potential future non-autologous product, with further commercial milestone payments, profit split payments on co-promoted products and royalties on at least a portion of worldwide net sales, depending on whether Arcellx opts in to co-promote the future products. If additional future products are developed, Arcellx would be eligible to receive additional milestone payments, profit split payments on co-promoted products and royalties on at least a portion of worldwide net sales, depending on whether Arcellx opts in to co-promote these additional future products as well.

In April 2022, we entered into a strategic research collaboration agreement (the “Dragonfly Collaboration Agreement”) with Dragonfly Therapeutics, Inc. (“Dragonfly”) to develop natural killer (“NK”) cell engager-based immunotherapies for oncology and inflammation indications. Under the terms of the Dragonfly Collaboration Agreement, we received an exclusive, worldwide license from Dragonfly for the 5T4-targeting investigational immunotherapy program, DF7001, as well as options, after the completion of certain preclinical activities, to license exclusive, worldwide rights to develop and commercialize additional NK cell engager programs using the Dragonfly Tri-specific NK Engager platform. Upon the closing of the Dragonfly Collaboration Agreement, we made a $300 million upfront payment to Dragonfly, and we made an additional $15 million payment related to a target selection in connection with an August 2022 amendment to the agreement, which were recorded in Acquired in-process research and development expenses on our Consolidated Statements of Income during the year ended December 31, 2022. In July 2023, we mutually agreed to terminate the DF7001 program. If we exercise our options on additional NK cell engager programs, Dragonfly would be eligible to receive opt-in payments and performance-based development, regulatory and commercial milestone payments and royalties on worldwide net sales on these optioned programs.

On March 13, 2021, we entered into a license and collaboration agreement with Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc. (“Merck”) to jointly develop and commercialize long-acting investigational treatments in HIV that combine Gilead’s investigational capsid inhibitor, lenacapavir, and Merck’s investigational nucleoside reverse transcriptase translocation inhibitor, islatravir, with other formulations potentially added to the collaboration as mutually agreed. The collaboration is initially focused on long-acting oral and injectable formulations.

Under the terms of the agreement, as amended, Gilead and Merck will mostly share global development and commercialization costs at 60% and 40%, respectively, across the oral and injectable formulation programs. For long-acting oral products, if approved, Gilead would lead commercialization in the U.S., and Merck would lead commercialization in the European Union (“EU”) and rest of the world. For long-acting injectable products, if approved, Merck would lead commercialization in the U.S. and Gilead would lead commercialization in the EU and rest of the world. Under the terms of the agreement, Gilead and Merck would jointly promote the combination products in the U.S. and certain other major markets. If successful, we would share global product revenues with Merck equally until product revenues surpass certain pre-determined per formulation revenue tiers. Upon passing $2.0 billion in net product sales for the oral combination in a given calendar year, our share of revenue would increase to 65% for any revenues above the threshold for such calendar year. Upon passing $3.5 billion in net product sales for the injectable combination in a given calendar year, our share of revenue will increase to 65% for any revenues above the threshold for such calendar year. Reimbursements of R&D costs to or from Merck are recorded within Research and development expenses on our Consolidated Statements of Income. Expenses recognized under the agreement were not material for the years ended December 31, 2023, 2022 and 2021. No revenues have been recognized under the agreement for the years ended December 31, 2023, 2022 and 2021.

We will also have the option to license certain of Merck’s investigational oral integrase inhibitors to develop in combination with lenacapavir. Reciprocally, Merck will have the option to license certain of Gilead’s investigational oral integrase inhibitors to develop in combination with islatravir. Each company may exercise its option for such investigational oral integrase inhibitor of the other company within the first five years after execution of the agreement, following completion of the first Phase 1 clinical trial of that integrase inhibitor. Upon exercise of an option, the companies will split development costs and revenues, unless the non-exercising company decides to opt out, in which case the non-exercising company will be paid a royalty.

On May 27, 2020, we entered into a transaction with Arcus, a publicly traded oncology-focused biopharmaceutical company, which included entry into an option, license and collaboration agreement (the “Collaboration Agreement”), with Gilead having the right to opt in to all current and future clinical-stage product candidates for up to ten years following the closing of the transaction, and a common stock purchase agreement and an investor rights agreement (together, and as subsequently amended the “Stock Purchase Agreements”).

In November 2021, we exercised our options to three of Arcus’ clinical stage programs and amended the Collaboration Agreement. The option exercise and amendment transaction closed in December 2021, triggering collaboration opt-in payments of $725 million and waiving the $100 million option continuation payment which would have been due to Arcus in the third quarter of 2022. The net option charge of $625 million was included within Acquired in-process research and development expenses on our Consolidated Statements of Income for the year ended December 31, 2021. The collaboration opt-in payments of $725 million were recorded in Other current liabilities on our Consolidated Balance Sheets as of December 31, 2021 and paid to Arcus in January 2022. Our payments to Arcus were included within Net cash used in investing activities on our Consolidated Statements of Cash Flows in the first quarter of 2022.

In May 2023, we again amended the Collaboration Agreement to initiate research programs against up to four targets jointly selected by the parties that are applicable to inflammatory diseases. As part of the amendment, we paid a $35 million upfront fee, which was charged to Acquired in-process research and development expenses on our Consolidated Statements of Income. Gilead may exercise an option to license each program at two separate, prespecified time points. If Gilead exercises its option at the earlier time point for the first two target programs, Arcus would be eligible to receive up to $420 million in future option and milestone payments and tiered royalties for each optioned program. For any other option exercise by Gilead for the four target programs, the parties would have rights to co-develop and share global development costs and to co-commercialize and share profits in the U.S. for optioned programs.

Under the amended Collaboration Agreement, the companies co-develop and share the global costs related to these clinical programs. We recorded $189 million and $187 million of such costs in Research and development expenses on our Consolidated Statements of Income for the years ended December 31, 2023 and 2022, respectively. If the optioned molecules achieve regulatory approval, the companies will co-commercialize and equally share profits in the U.S. Gilead will hold exclusive commercialization rights outside the U.S., subject to any rights of Arcus’s existing collaboration partners, and will pay to Arcus tiered royalties as a percentage of net sales ranging from the mid teens to low twenties. Under the amended Collaboration Agreement, we may also pay an additional $100 million at our option on each of the fourth, sixth and eighth anniversaries of the agreement, unless terminated early, to maintain the rights to opt in to future Arcus programs for the duration of the contact term.

Under the Stock Purchase Agreements, we have the right to purchase from Arcus additional shares up to a maximum of 35% of the outstanding voting stock of Arcus over a five-year period ending in the third quarter of 2025. We were also subject to a three-year standstill, restricting certain other activity on our part, which expired in the second quarter of 2023. We have made various purchases of shares since the original closing of the agreement and, following our latest purchase in the second quarter of 2023, we owned a total of 14.8 million shares, which represented approximately 19.9% of the issued and outstanding voting stock of Arcus at that time. As of December 31, 2023, we had two designees on Arcus’ board of directors.

In June 2020, we entered into a transaction with Pionyr Immuotherapeutics (“Pionyr”), a privately held company pursuing novel biology in the field of immuno-oncology, which included entry into two separate agreements, one related to the initial acquisition of a 49.9% equity interest in Pionyr, and the other providing us the exclusive option, subject to certain terms and conditions, to acquire the remaining outstanding capital stock of Pionyr (the “Pionyr Merger and Option Agreements”) and a R&D service agreement.

In March 2023, we terminated the R&D service agreement, waived our exclusive option to acquire Pionyr and certain other rights under the Pionyr Merger and Option Agreements and recorded a $70 million charge to Other income (expense), net on our Consolidated Statements of Income, writing off the full value of the option that had previously been recorded in Other long-term assets on our Consolidated Balance Sheets.

We previously accounted for our investment in Pionyr using the equity method of accounting because our equity interest provided us with the ability to exercise significant influence over Pionyr. The carrying value of our equity method investment in Pionyr was zero as of December 31, 2022. In August 2023, Pionyr was acquired by Ikena Oncology, Inc. (“Ikena”), a publicly traded company, and our equity interest was converted to shares of Ikena stock.

In July 2020, we entered into a transaction with Tizona Therapeutics, Inc. (“Tizona”), a privately held company developing cancer immunotherapies, which included entry into two separate agreements, one related to the initial acquisition of a 49.9% equity interest in Tizona, and the other providing us the exclusive option, subject to certain terms and conditions, to acquire the remaining outstanding capital stock of Tizona (the “Tizona Merger and Option Agreements”) and a development agreement.

In September 2023, we terminated the development agreement, waived our exclusive option to acquire Tizona and certain other rights under the Tizona Merger and Option Agreements and recorded a $41 million charge to Other income (expense), net on our Consolidated Statements of Income, writing off the full value of the option that had previously been recorded in Other long-term assets on our Consolidated Balance Sheets.

In October 2023, we amended a previous agreement with Galapagos, a clinical-stage biotechnology company based in Belgium, related to the development and commercialization of filgotinib, a JAK1-selective inhibitor being evaluated for inflammatory disease indications, to terminate the global development cost-sharing arrangement and Galapagos’ obligation to pay tiered royalties to us on net sales in Europe. As a result, we wrote off the remaining $51 million balance of our related finite-lived intangible asset as discussed in Note 9. Goodwill and Intangible Assets. We had also previously paid Galapagos €160 million (or approximately $190 million) related to an agreement to terminate Galapagos’ right to receive any future milestone payments relating to filgotinib in Europe, with the full amount being expensed in 2020 and €110 million (or approximately $130 million) paid in 2021 and €50 million (or approximately $60 million) paid in 2022.

Pursuant to the Galapagos Subscription Agreement, we purchased 6.8 million new ordinary shares of Galapagos and were issued warrants that confer the right to subscribe, from time to time, for a number of new shares to be issued by Galapagos sufficient to bring the number of shares owned by us to 29.9% of the issued and outstanding shares at the time of our exercises. We currently own 16.7 million shares or approximately 25.8% of the shares issued and outstanding at the time of last purchase in 2019. We are subject to a 10-year standstill restricting our ability to acquire voting securities of Galapagos exceeding more than 29.9% of the then-issued and outstanding voting securities of Galapagos. We agreed not to, without the prior consent of Galapagos, dispose of any equity securities of Galapagos prior to the second anniversary of the closing of the Galapagos Subscription Agreement or dispose of any equity securities of Galapagos thereafter until the fifth anniversary of the closing of the Galapagos Subscription Agreement, if after such disposal we would own less than 20.1% of the then-issued and outstanding voting securities of Galapagos, subject to certain exceptions and termination events. In April 2021, we amended the Galapagos Subscription Agreement to extend the initial lock-up provision for certain Galapagos shares from August 2021 to August 2024.

With respect to programs in Galapagos’ current and future pipeline, if we exercise our option to a program, we will pay a $150 million option exercise fee per program. In addition, Galapagos will receive tiered royalties ranging from 20% to 24% on net sales in our territories of each Galapagos product optioned by us. If we exercise our option for a program, the parties will share equally in development costs and mutually agreed commercialization costs incurred subsequent to our exercise of the option. We may terminate the collaboration in its entirety or on a program-by-program and country-by-country basis with advance notice as well as following other customary termination events. We have two designees appointed to Galapagos’ board of directors.

In 2009, we entered into a license and collaboration agreement with Janssen to develop and commercialize a fixed-dose combination of our Truvada and Janssen’s non-nucleoside reverse transcriptase inhibitor, rilpivirine. This combination was approved in the U.S. and EU in 2011, and is sold under the brand name Complera in the U.S. and Eviplera in the EU. The agreement was amended in 2014 to expand the collaboration to include another product containing Janssen’s rilpivirine and our emtricitabine and tenofovir alafenamide (“Odefsey”).

Under the financial provisions of the 2014 amendment, the selling party sets the price of the combined products and the parties share revenues based on the ratio of the net selling prices of the party’s component(s), subject to certain restrictions and adjustments. We retain a specified percentage of Janssen’s share of revenues, including up to 30% in major markets. Sales of these products are included in Product sales and Janssen’s share of revenues is included in Cost of goods sold on our Consolidated Statements of Income. Cost of goods sold relating to Janssen’s share was $430 million, $483 million and $530 million for the years ended December 31, 2023, 2022 and 2021, respectively.

Termination of the agreement may be on a product or country basis and will depend on the circumstances, including withdrawal of a product from the market, material breach by either party or expiry of the revenue share payment term. We may terminate the agreement without cause with respect to the countries where we sell the products, in which case Janssen has the right to become the selling party for such country if the product has launched but has been on the market for fewer than 10 years.

Under the terms of the 2014 amendment, we granted Janssen an exclusive license to Symtuza worldwide. Janssen is responsible for manufacturing, registration, distribution and commercialization of Symtuza worldwide. We are responsible for the intellectual property related to the Gilead Compounds and are the exclusive supplier of the Gilead Compounds. Neither party is restricted from combining its drugs with any other drug products except those which are similar to the components of Symtuza.

Janssen sets the price of Symtuza and the parties share revenue based on the ratio of the net selling prices of the party’s component(s), subject to certain restrictions and adjustments. The intellectual property license and supply obligations related to the Gilead Compounds are accounted for as a single performance obligation. As the license was deemed to be the predominant item to which the revenue share relates, we recognize our share of the Symtuza revenue in the period when the corresponding sales of Symtuza by Janssen occur. We record our share of the Symtuza revenue as Product sales on our Consolidated Statements of Income primarily because we supply the Gilead Compounds to Janssen for Symtuza.

Termination of the agreement may be on a product or country basis and will depend on the circumstances, including withdrawal of a product from the market, material breach by either party or expiry of the revenue share payment term. Janssen may terminate the agreement without cause on a country-by-country basis, in which case Gilead has the right to become the selling party for such country(ies) if the product has launched but has been on the market for fewer than 10 years. Janssen may also terminate the entire agreement without cause.

In 2005, Japan Tobacco, Inc. (“Japan Tobacco”) granted us exclusive rights to develop and commercialize elvitegravir, a novel HIV integrase inhibitor, in all countries of the world, excluding Japan, where Japan Tobacco retained such rights. Effective December 2018, we entered into an agreement with Japan Tobacco to acquire the rights to market and distribute certain products in our HIV portfolio in Japan and to expand our rights to develop and commercialize elvitegravir to include Japan. We are responsible for the marketing of the products as of January 1, 2019.

We are responsible for seeking regulatory approval in our territories and are required to use diligent efforts to commercialize elvitegravir for the treatment of HIV infection. We bear all costs and expenses associated with such commercialization efforts and pay a royalty to Japan Tobacco based on our product sales. Our sales of these products are included in Product sales on our Consolidated Statements of Income. Royalties due to Japan Tobacco are included in Cost of goods sold on our Consolidated Statements of Income. Royalty expenses recognized were $167 million, $198 million and $250 million for the years ended December 31, 2023, 2022 and 2021, respectively.

Under the terms of the 2018 agreement, we paid Japan Tobacco $559 million in cash and recognized an intangible asset of $550 million reflecting the estimated fair value of the marketing-related rights acquired from Japan Tobacco. The intangible asset is being amortized over nine years, representing the period over which the majority of the benefits are expected to be derived from the applicable products in our HIV portfolio. The amortization expense is classified as selling expense and recorded as Selling, general and administrative expenses on our Consolidated Statements of Income.

In April 2019, Everest Medicines (“Everest”) and Immunomedics entered into an agreement granting Everest an exclusive license to develop and commercialize Trodelvy in Greater China, South Korea, Singapore, Indonesia, Philippines, Vietnam, Thailand, Malaysia and Mongolia (the “Territories”). Gilead subsequently acquired Immunomedics in October 2020 and assumed the Everest license and supply agreement, which provided for certain sales milestones and royalties payments to be made to Gilead and was recorded as a $175 million finite-lived asset as part of the purchase accounting. In the fourth quarter of 2022, we reacquired all development and commercialization rights for Trodelvy from Everest and terminated the previous agreement. Under the terms of the new agreement, Gilead made $280 million in upfront termination payments to Everest, of which $84 million was made in 2022 and $196 million was made in 2023. In addition, Everest is eligible to receive up to $175 million in potential additional payments upon achievement of certain regulatory and commercial milestones. We accounted for the new agreement as a contract termination, which includes the reacquisition of commercial rights and the settlement of our pre-existing relationship with Everest. As a result, we recorded an expense of $406 million in Selling, general and administrative expenses on our Consolidated Statements of Income during the year ended December 31, 2022, which primarily represents the upfront costs and write-off of the remaining value of the pre-existing asset related to the prior agreement. Simultaneously, we recorded an acquired finite-lived asset with a fair value of $50 million for the commercial rights reacquired for products approved in the Territories.

In December 2023, we entered into an arrangement with funds managed by Abingworth LLP (“Abingworth”) under which we will receive up to $210 million to co-fund our development costs for Trodelvy for non-small cell lung cancer in 2023 through 2026. As there is substantive transfer of risk to the financial partner, the development funding is recognized by us as an obligation to perform contractual services. In 2023, we received $50 million from Abingworth. We are recognizing the funding as a reduction of Research and development expenses using an attribution model over the period of the related expenses. If successful, upon regulatory approval in the U.S. for the specified indication, Abingworth will be eligible to receive an approval-based fixed milestone payment of up to $84 million and royalties based on the applicable net sales.