Gilead Sciences Inc.: 10-K Risk Factor Changes

We may be unable to accurately predict demand for our products as demand depends on a number of factors. If we do not accurately forecast demand or manufacture products at levels to align with actual demand, then we may experience product shortages or build excess inventory that may need to be written off. For example, product demand may be adversely affected if physicians do not see the benefit of our products. Additionally, uptake of new products may not materialize as expected, or at all in the case of unsuccessful product candidates. For example, Veklury sales generally reflect COVID-19 related rates and severity of infections and hospitalizations, as well as the availability, uptake and effectiveness of vaccines and alternative treatments for COVID-19, and future sales in the short- and long-term remain uncertain. Additionally, the non-retail sector in the U.S., which includes government institutions, including state AIDS Drug Assistance Programs, the U.S. Department of Veterans Affairs, correctional facilities and large health maintenance organizations, tends to be less consistent in terms of buying patterns and often causes quarter-over-quarter fluctuations that do not mirror actual patient demand for our products. Federal and state budget pressures, as well as the annual grant cycles for federal and state funds, may cause purchasing patterns to not reflect patient demand for our products. We expect to continue to experience fluctuations in the purchasing patterns of our non-retail customers. In light of the budget crises faced by many European countries, we have observed variations in purchasing patterns induced by cost containment measures in Europe. We believe these measures have caused some government agencies and other purchasers to reduce inventory of our products in the distribution channels, and we may continue to see this trend in the future. We sell and distribute most of our products in the U.S. exclusively through the wholesaler/distributor channel. Historically, approximately 90% of our product sales in the U.S. have been to three wholesalers, Cardinal Health, Inc., Cencora, Inc., and McKesson Corporation, and their specialty distributor affiliates. The U.S. wholesalers and distributors with whom we have entered into inventory management agreements make estimates to determine end-user demand and may not be accurate in matching their inventory levels to actual end-user demand. As a result, changes in inventory levels held by those wholesalers and distributors can cause our operating results to fluctuate unexpectedly if our sales to these wholesalers and distributors do not match end-user demand. In addition, inventory is held at retail and specialty pharmacies and other non-wholesaler/distributor locations with whom we have no inventory management agreements and no control over buying patterns. Adverse changes in economic conditions, increased competition or other factors may cause retail and specialty pharmacies to reduce their inventories of our products, which would reduce their orders from wholesalers and distributors and, consequently, the wholesalers’ and distributors’ orders from us, even if end-user demand has not changed. In addition, we have observed that strong wholesaler/distributor and sub-wholesaler/distributor purchases of our products in the second half of the year typically results in inventory draw-down by wholesalers/distributors and sub-wholesalers/distributors in the subsequent first quarter. As inventory in the distribution channel fluctuates from quarter to quarter, we may continue to see fluctuations in our earnings and a mismatch between prescription demand for our products and our revenues. 18 18 18

We may be unable to accurately predict demand for our products, including the uptake of new products, as demand depends on a number of factors. For example, product demand may be adversely affected if physicians do not see the benefit of our products. Additionally, the non-retail sector in the U.S., which includes government institutions, including state AIDS Drug Assistance Programs, the U.S. Department of Veterans Affairs, correctional facilities and large health maintenance organizations, tends to be less consistent in terms of buying patterns and often causes quarter-over-quarter fluctuations that do not mirror actual patient demand for our products. Federal and state budget pressures, as well as the annual grant cycles for federal and state funds, may cause purchasing patterns to not reflect patient demand for our products. We expect to continue to experience fluctuations in the purchasing patterns of our non-retail customers. In light of the budget crises faced by many European countries, we have observed variations in purchasing patterns induced by cost containment measures in Europe. We believe these measures have caused some government agencies and other purchasers to reduce inventory of our products in the distribution channels, and we may continue to see this trend in the future. 18 18 18 We sell and distribute most of our products in the U.S. exclusively through the wholesale channel. For the year ended December 31, 2023, approximately 91% of our product sales in the U.S. were to three wholesalers, Cencora, Inc. (formerly known as AmerisourceBergen Corporation), Cardinal Health, Inc. and McKesson Corporation. The U.S. wholesalers with whom we have entered into inventory management agreements make estimates to determine end-user demand and may not be accurate in matching their inventory levels to actual end-user demand. As a result, changes in inventory levels held by those wholesalers can cause our operating results to fluctuate unexpectedly if our sales to these wholesalers do not match end-user demand. In addition, inventory is held at retail pharmacies and other non-wholesaler locations with whom we have no inventory management agreements and no control over buying patterns. Adverse changes in economic conditions, increased competition or other factors may cause retail pharmacies to reduce their inventories of our products, which would reduce their orders from wholesalers and, consequently, the wholesalers’ orders from us, even if end-user demand has not changed. In addition, we have observed that strong wholesaler and sub-wholesaler purchases of our products in the second half of the year typically results in inventory draw-down by wholesalers and sub-wholesalers in the subsequent first quarter. As inventory in the distribution channel fluctuates from quarter to quarter, we may continue to see fluctuations in our earnings and a mismatch between prescription demand for our products and our revenues.

Some institutional and individual investors continue to use environmental, social and governance (“ESG”) screening criteria to determine whether Gilead qualifies for inclusion in their investment portfolios. We are frequently asked by investors and other stakeholders to set ambitious ESG goals and provide new and more robust disclosure on goals, progress toward goals and other matters of interest to ESG stakeholders. In response, we have adapted the tracking and reporting of our corporate responsibility program to various evolving ESG frameworks, and we have established and announced goals and other objectives related to ESG matters. These goal statements reflect our current plans and aspirations and are not guarantees that we will be able to achieve them. Our efforts to accomplish and accurately report on these goals and objectives present numerous operational, reputational, financial, legal and other risks, any of which could have a material negative impact, including on our reputation and stock price. Our ability to achieve any corporate responsibility goal or objective is subject to numerous risks, many of which are outside of our control. Examples of such risks include: (1) the availability and cost of low- or non-carbon-based energy sources and technologies, (2) evolving regulatory requirements affecting ESG standards or disclosures, (3) the availability of suppliers that can meet our corporate responsibility and related standards, (4) our ability to recruit, develop and retain qualified talent in our labor markets and (5) the impact of our organic growth and acquisitions or dispositions of businesses or operations. 27 27 27 The standards for tracking and reporting on ESG matters are relatively new, have not been harmonized and continue to evolve. Our selection of disclosure frameworks that seek to align with various reporting standards may change from time to time and may result in a lack of consistent or meaningful comparative data from period to period. In addition, regulatory authorities have begun to impose mandatory disclosure requirements with respect to ESG matters, such as regulations proposed or adopted by federal agencies related to climate-related disclosures, claims, practices or initiatives, the EU’s Corporate Sustainability Reporting Directive, and California’s Climate-Related Financial Risk Act and the Climate Corporate Data Accountability Act. Our processes and controls may not reflect evolving standards for identifying, measuring and reporting ESG matters, immediately or at all, our interpretation of reporting standards may differ from those of others, and such standards may change over time, any of which could result in significant revisions to our goals or reported progress in achieving such goals. In addition, enhancements to our processes and controls to reflect evolving reporting standards may be costly and require additional resources. Investor and other stakeholder expectations and standards for ESG practices are varied and evolving, and may be inconsistent with our ESG practices. It is not possible for our ESG practices to satisfy all investors and stakeholders, and our reputation, our ability to attract or retain employees and our attractiveness as an investment, business partner or acquiror could be negatively impacted. Similarly, our pursuit of ESG practices, as well as our failure or perceived failure to pursue or fulfill our goals, targets and objectives, or to satisfy various reporting standards within the timelines we announce, or at all, could also have similar negative impacts and expose us to government enforcement actions, stakeholder criticism or negative campaigns, and private litigation.

Institutional and individual investors are increasingly using ESG screening criteria to determine whether Gilead qualifies for inclusion in their investment portfolios. We are frequently asked by investors and other stakeholders to set ambitious ESG goals and provide new and more robust disclosure on goals, progress toward goals and other matters of interest to ESG stakeholders. In response, we have adapted the tracking and reporting of our corporate responsibility program to various evolving ESG frameworks, and we have established and announced goals and other objectives related to ESG matters. These goal statements reflect our current plans and aspirations and are not guarantees that we will be able to achieve them. Our efforts to accomplish and accurately report on these goals and objectives present numerous operational, reputational, financial, legal and other risks, any of which could have a material negative impact, including on our reputation and stock price. Our ability to achieve any goal or objective, including with respect to environmental and diversity initiatives, is subject to numerous risks, many of which are outside of our control. Examples of such risks include: (1) the availability and cost of low- or non-carbon-based energy sources and technologies, (2) evolving regulatory requirements affecting ESG standards or disclosures, (3) the availability of suppliers that can meet our sustainability, diversity and other standards, (4) our ability to recruit, develop and retain diverse talent in our labor markets and (5) the impact of our organic growth and acquisitions or dispositions of businesses or operations. The standards for tracking and reporting on ESG matters are relatively new, have not been harmonized and continue to evolve. Our selection of disclosure frameworks that seek to align with various reporting standards may change from time to time and may result in a lack of consistent or meaningful comparative data from period to period. In addition, regulatory authorities may impose mandatory disclosure requirements with respect to ESG matters. For example, in March 2022, U.S. Securities and Exchange Commission (“SEC”) proposed rule changes that would require companies to make certain climate-related disclosures, including information about climate-related risks, greenhouse gas emissions and certain climate-related financial statement metrics. Also, in October 2023, the California Governor signed the Climate-Related Financial Risk Act and the Climate Corporate Data Accountability Act into law, which impose significant and mandatory climate-related reporting requirements for large companies doing business in the state. Our processes and controls may not reflect evolving standards for identifying, measuring and reporting ESG matters, immediately or at all, our interpretation of reporting standards may differ from those of others, and such standards may change over time, any of which could result in significant revisions to our goals or reported progress in achieving such goals. In addition, enhancements to our processes and controls to reflect evolving reporting standards may be costly and require additional resources. If our ESG practices do not meet evolving investor or other stakeholder expectations and standards, then our reputation, our ability to attract or retain employees and our attractiveness as an investment, business partner or acquiror could be negatively impacted. Similarly, our failure or perceived failure to pursue or fulfill our goals, targets and objectives or to satisfy various reporting standards within the timelines we announce, or at all, could also have similar negative impacts and expose us to government enforcement actions and private litigation.

HIV We receive a substantial portion of our revenue from sales of our products for the treatment and prevention of HIV infection. We may be unable to sustain or increase sales of our HIV products for any number of reasons, including market share gains by competitive products, including generics, or the inability to introduce new HIV medications necessary to remain competitive. In such case, we may need to scale back our operations, including our future drug development and spending on research and development (“R&D”) efforts. For example, many of our HIV products contain tenofovir alafenamide (“TAF”), which belongs to the nucleoside class of antiviral therapeutics. If there are any changes to the treatment or prevention paradigm for HIV, and nucleoside-based therapeutics do not remain the preferred regimen, our HIV product sales would be adversely impacted. Cell Therapy Advancing a novel and personalized therapy such as Yescarta or Tecartus, which are chimeric antigen receptor (“CAR”) T-cell therapies, creates significant challenges, including: •educating and certifying medical personnel regarding the procedures and the potential side effects, such as cytokine release syndrome and neurologic toxicities, in compliance with the Risk Evaluation and Mitigation Strategy program required by the U.S. Food and Drug Administration (“FDA”); •securing sufficient supply of other medications to manage side effects, such as tocilizumab and corticosteroids, which may not be available in sufficient quantities, may not adequately control the side effects and/or may have detrimental impacts on the efficacy of cell therapy; •developing and maintaining a robust and reliable process for engineering a patient’s T cells in our facilities and infusing them back into the patient; and •conditioning patients with chemotherapy in advance of administering our therapy, which may increase the risk of adverse side effects. The use of engineered T cells as a potential cancer treatment is a recent development and may not be broadly accepted by physicians, patients, hospitals, cancer treatment centers, payers and others in the medical community. For example, in January 2024, FDA instituted a class labeling change for all approved CAR T-cell therapies, including a “boxed warning” about the possible risk of secondary T-cell malignancies in patients treated with CAR T-cell therapy. For challenges related to the reimbursement of Yescarta and Tecartus, see also “Our existing products are subject to reimbursement pressures from government agencies and other third parties, required rebates and discounts, and other pricing pressures.” We rely on third-party sites to collect patients’ white blood cells, known as apheresis centers, as well as shippers, couriers, and hospitals for the logistical collection of patients’ white blood cells and ultimate delivery of Yescarta and Tecartus to patients. These vendors may encounter disruptions or difficulties that could result in product loss and regulatory action. Apheresis centers may also choose not to participate in our quality certification process, or we may be unable to complete such certification in a timely manner or at all, which could delay or constrain our manufacturing and commercialization efforts. 17 17 17 We also face risks related to our in-house CAR T-cell therapy manufacturing facilities in California, Maryland and the Netherlands, spanning process development, vector manufacturing, clinical trial production and commercial product manufacturing. Quality, reliability and speed are critical in cell therapy manufacturing to quickly and safely deliver our cell therapies to patients. Any delays or quality issues with our manufacturing operations could adversely affect our business and damage our reputation. In addition, we may not be able to sufficiently increase manufacturing network capacity to meet growing demand.

HIV We receive a substantial portion of our revenue from sales of our products for the treatment and prevention of HIV infection. During the year ended December 31, 2023, sales of our HIV products accounted for approximately 67% of our total product sales. We may be unable to sustain or increase sales of our HIV products for any number of reasons, including market share gains by competitive products, including generics, or the inability to introduce new HIV medications necessary to remain competitive. In such case, we may need to scale back our operations, including our future drug development and spending on research and development (“R&D”) efforts. For example, many of our HIV products contain tenofovir alafenamide (“TAF”), which belongs to the nucleoside class of antiviral therapeutics. If there are any changes to the treatment or prevention paradigm for HIV, and nucleoside-based therapeutics do not remain the preferred regimen, our HIV product sales would be adversely impacted. Veklury We face risks related to our supply and sale of Veklury, which was approved by U.S. Food and Drug Administration (“FDA”) as a treatment for patients with coronavirus disease 2019 (“COVID-19”). Veklury sales generally reflect COVID-19 related rates and severity of infections and hospitalizations, as well as the availability, uptake and effectiveness of vaccines and alternative treatments for COVID-19. In May 2023, the World Health Organization declared the end of COVID-19 as a public health emergency of international concern. Future sales of Veklury in the short- and long-term remain uncertain. If we do not accurately forecast demand or manufacture Veklury at levels to align with actual demand, then we may experience product shortages or build excess inventory that may need to be written off. Cell Therapy Advancing a novel and personalized therapy such as Yescarta or Tecartus, which are chimeric antigen receptor (“CAR”) T-cell therapies, creates significant challenges, including: •educating and certifying medical personnel regarding the procedures and the potential side effects, such as cytokine release syndrome and neurologic toxicities, in compliance with the Risk Evaluation and Mitigation Strategy program required by FDA; •securing sufficient supply of other medications to manage side effects, such as tocilizumab and corticosteroids, which may not be available in sufficient quantities, may not adequately control the side effects and/or may have detrimental impacts on the efficacy of cell therapy; •developing and maintaining a robust and reliable process for engineering a patient’s T cells in our facilities and infusing them back into the patient; and •conditioning patients with chemotherapy in advance of administering our therapy, which may increase the risk of adverse side effects. 17 17 17 The use of engineered T cells as a potential cancer treatment is a recent development and may not be broadly accepted by physicians, patients, hospitals, cancer treatment centers, payers and others in the medical community. While FDA has approved some cell therapies, including Yescarta and Tecartus, we must continue to demonstrate to the medical community the potential advantages of cell therapy compared to existing and future therapeutics. In November 2023, FDA announced that it is investigating the risk of T-cell malignancies in patients who received treatment with CAR T-cell therapy, noting that the overall benefits of CAR T-cell therapy products continue to outweigh their potential risks for their approved uses. In January 2024, FDA determined that safety labeling issues were needed for approved CAR T-cell therapies, including a “boxed warning” about the possible risk of T-cell malignancies in patients treated with CAR T-cell therapy. Additionally, FDA requested continued monitoring and reporting of cases of secondary cancers. For challenges related to the reimbursement of Yescarta and Tecartus, see also “Our existing products are subject to reimbursement pressures from government agencies and other third parties, required rebates and discounts, and other pricing pressures.” We rely on third-party sites to collect patients’ white blood cells, known as apheresis centers, as well as shippers, couriers, and hospitals for the logistical collection of patients’ white blood cells and ultimate delivery of Yescarta and Tecartus to patients. These vendors may encounter disruptions or difficulties that could result in product loss and regulatory action. Apheresis centers may also choose not to participate in our quality certification process, or we may be unable to complete such certification in a timely manner or at all, which could delay or constrain our manufacturing and commercialization efforts. We also face risks related to our in-house CAR T-cell therapy manufacturing facilities in California, Maryland and the Netherlands, spanning process development, vector manufacturing, clinical trial production and commercial product manufacturing. Quality, reliability and speed are critical in cell therapy manufacturing to quickly and safely deliver our cell therapies to patients. Any delays or quality issues with our manufacturing operations could adversely affect our business and damage our reputation. In addition, we may not be able to sufficiently increase manufacturing network capacity to meet growing demand.

The healthcare industry is subject to various federal, state and international laws and regulations pertaining to drug approval, manufacturing, reimbursement, rebates, price reporting, healthcare fraud and abuse, and data privacy and security. In the U.S., these laws include anti-kickback and false claims laws, the Federal Food, Drug, and Cosmetic Act, laws and regulations relating to the Medicare and Medicaid programs and other federal and state programs, such as the Medicaid Rebate Statute and the 340B statute, laws that regulate written and verbal communications about our products, individual state laws relating to pricing and sales and marketing practices, the Health Insurance Portability and Accountability Act and other federal and state laws relating to the privacy and security of health information, including the Executive Order on Preventing Access to Americans’ Bulk Sensitive Personal Data, which may impact how and where clinical and other sensitive data is shared, accessed and analyzed, and United States Government-Related Data by Countries of Concern issued in February 2024. Actual or alleged violations of these laws or any related regulations may be punishable by criminal and/or civil sanctions, including, in some instances, substantial fines, civil monetary penalties, exclusion from participation in federal and state healthcare programs, including Medicare, Medicaid and U.S. Department of Veterans Affairs and U.S. Department of Defense health programs, actions against executives overseeing our business and significant remediation measures, negative publicity or other consequences. These laws and regulations are broad in scope and subject to changing and evolving interpretations, including as a result of legal challenges, which may increase following the U.S. Supreme Court decision to overrule the Chevron doctrine, any of which could require us to incur substantial costs associated with compliance, alter one or more of our sales or marketing practices, or impact our ability to obtain or maintain regulatory approvals. The resulting impact on our business is uncertain and could be material. Additionally, recently proposed legislation in the U.S., such as the BIOSECURE Act (which, among other things, could prohibit U.S. executive agencies from contracting with, or expending loans or granting funds to, companies that use biotechnology equipment or services for certain activities from certain foreign-owned entities), has the potential to adversely impact our ability to receive equipment or services from such entities, including certain of which we use in connection with our clinical trials and our clinical and commercial manufacturing, which could increase the cost or limit the supply of material available to us, delay the procurement or supply of such material, delay or impact clinical trials and regulatory submissions, delay the launch of commercial products and adversely affect our financial condition and business prospects. In addition, government price reporting and payment regulations are complex, and we are continually assessing the methods by which we calculate and report pricing in accordance with these obligations. Our methodologies for calculations are inherently subject to assumptions and may be subject to review and challenge by various government agencies, which may disagree with our interpretation. If the government disagrees with our reported calculations, we may need to restate previously reported data and could be subject to additional financial and legal liability. There also continues to be enhanced scrutiny of company-sponsored patient assistance programs, including co-pay assistance programs and manufacturer donations to third-party charities that provide such assistance. There has also been enhanced scrutiny by governments on reimbursement support offerings and other patient support offerings, clinical education programs and promotional speaker programs. Despite our training and compliance program, our internal control policies and procedures may not protect us from unlawful acts committed by our employees or agents. If we, or our agents and vendors, are deemed to have failed to comply with laws, regulations or government guidance in any of these areas, we could be subject to criminal or civil sanctions. Any similar violations by our competitors could also negatively impact our industry’s reputation and increase scrutiny over our business and our products. For a description of our government investigations and related litigation, see Note 13. Commitments and Contingencies of the Notes to Consolidated Financial Statements included in Part II, Item 8 of this Annual Report on Form 10-K.

The healthcare industry is subject to various federal, state and international laws and regulations pertaining to drug approval, reimbursement, rebates, price reporting, healthcare fraud and abuse, and data privacy and security. In the U.S., these laws include anti-kickback and false claims laws, Federal Food, Drug, and Cosmetic Act, laws and regulations relating to the Medicare and Medicaid programs and other federal and state programs, such as the Medicaid Rebate Statute and the 340B statute, laws that regulate written and verbal communications about our products, individual state laws relating to pricing and sales and marketing practices, the Health Insurance Portability and Accountability Act and other federal and state laws relating to the privacy and security of health information. Actual or alleged violations of these laws or any related regulations may be punishable by criminal and/or civil sanctions, including, in some instances, substantial fines, civil monetary penalties, exclusion from participation in federal and state healthcare programs, including Medicare, Medicaid and U.S. Department of Veterans Affairs and U.S. Department of Defense health programs, actions against executives overseeing our business and significant remediation measures, negative publicity or other consequences. These laws and regulations are broad in scope and subject to changing and evolving interpretations, which could require us to incur substantial costs associated with compliance, alter one or more of our sales or marketing practices, or impact our ability to obtain or maintain regulatory approvals. The resulting impact on our business is uncertain and could be material. In addition, government price reporting and payment regulations are complex, and we are continually assessing the methods by which we calculate and report pricing in accordance with these obligations. Our methodologies for calculations are inherently subjective and may be subject to review and challenge by various government agencies, which may disagree with our interpretation. If the government disagrees with our reported calculations, we may need to restate previously reported data and could be subject to additional financial and legal liability. There also continues to be enhanced scrutiny of company-sponsored patient assistance programs, including co-pay assistance programs and manufacturer donations to third-party charities that provide such assistance. There has also been enhanced scrutiny by governments on reimbursement and other patient support offerings, clinical education programs and promotional speaker programs. If we, or our agents and vendors, are deemed to have failed to comply with laws, regulations or government guidance in any of these areas, we could be subject to criminal or civil sanctions. Any similar violations by our competitors could also negatively impact our industry reputation and increase scrutiny over our business and our products. For a description of our government investigations and related litigation, see Note 13. Commitments and Contingencies of the Notes to Consolidated Financial Statements included in Part II, Item 8 of this Annual Report on Form 10-K. 24 24 24

Many of our operations and facilities, including those essential to our manufacturing, R&D and commercialization/distribution activities, are located in regions subject to natural or man-made disasters, such as climate change, earthquakes, hurricanes, rising sea levels and flooding, fires, extreme heat, drought or other extreme weather conditions, or efforts taken by third parties to prevent or mitigate such disasters, such as public safety power shutoffs and facility shutdowns. The severity and frequency of weather-related events has been amplified, and is expected to continue to be amplified, by climate change. Such natural disasters have caused, and in the future may cause, damage to and/or disrupt our operations, which may result in a material adverse effect on our business and financial results. Additionally, our corporate headquarters in Foster City and certain R&D and manufacturing facilities are located in California, a region that is seismically active and prone to wildfires. Although we have business continuity plans and contingencies in place and conduct periodic assessments of our natural disaster risk as part of our overall enterprise risk management program, a major earthquake or other natural disaster can result in significant recovery time and a prolonged interruption to our operational and business activities. We may be required to incur significant costs to remedy the effects of such natural disasters and to resume or restore our operations, which could adversely impact us. Our suppliers and third-party manufacturers and corporate partners face similar risks, and any disruption to their operations could have an adverse effect on our manufacturing and supply chain. In addition, growing concern regarding climate change has resulted in an evolving legal and regulatory landscape, with new requirements enacted to prevent, mitigate or adapt to the implications of climate change. These regulations, which can differ across jurisdictions, subject us to many transition risks, including, for example, new or expanded carbon pricing or taxes, increased compliance costs, restrictions on greenhouse gas emissions, investment in new technologies, increased carbon disclosure and transparency, investments in data gathering and reporting systems, upgrades of facilities to meet new building codes and the redesign of utility systems, which could increase the company’s operating costs, including the cost of electricity and energy. For example, over 80 countries committed to the United Nations COP26 Health Programme’s initiatives on climate resilient and low carbon sustainable health systems. As such, there is an increasing expectation for the health sector to implement commitments to decarbonize and achieve net zero emissions by 2050, and we may be required to incur material costs in order to do so. Failure to sufficiently decarbonize or comply with climate-related requirements may threaten our ability to operate in certain geographies and negatively affect our business. At the same time, we may also face negative impacts from stakeholders who do not support climate-related initiatives or concerns. Regulatory efforts, both internationally and in the U.S., are evolving, including the international alignment of such efforts, and we cannot determine what final regulations will be enacted, modified or reversed or what their ultimate impact on our business will be. Our suppliers and third-party manufacturers and corporate partners face similar transition risks that could have an adverse effect on our business.

Many of our operations and facilities, including those essential to our manufacturing, R&D and commercialization/distribution activities, are located in regions subject to natural or man-made disasters, such as climate change, earthquakes, hurricanes, rising sea levels and flooding, fires, extreme heat, drought or other extreme weather conditions, or efforts taken by third parties to prevent or mitigate such disasters, such as public safety power shutoffs and facility shutdowns. The severity and frequency of weather-related events has been amplified, and is expected to continue to be amplified, by climate change. Such natural disasters have caused, and in the future may cause, damage to and/or disrupt our operations, which may result in a material adverse effect on our business and financial results. For example, our facility in Cork, Ireland, where we conduct commercial manufacturing, packaging and labeling and perform quality control testing and final release of many of our products, temporarily suspended on-site operations as a result of the flooding caused by Storm Babet in October 2023. Additionally, our corporate headquarters in Foster City and certain R&D and manufacturing facilities are located in California, a seismically active region. Although we have business continuity plans and contingencies in place and conduct periodic assessments of our natural disaster risk as part of our overall enterprise risk management program, a major earthquake or other natural disaster can result in significant recovery time and a prolonged interruption to our operational and business activities. We may be required to incur significant costs to remedy the effects of such natural disasters and to resume or restore our operations, which could adversely impact us. Our suppliers and third-party manufacturers and corporate partners face similar risks, and any disruption to their operations could have an adverse effect on our manufacturing and supply chain. Also, see risks under the headings “We may face manufacturing difficulties, delays or interruptions, including at our third-party manufacturers and corporate partners” and “We may not be able to obtain materials or supplies necessary to conduct clinical trials or to manufacture and sell our products, which could limit our ability to generate revenues. ” In addition, growing concern regarding climate change has resulted in an evolving legal and regulatory landscape, with new requirements enacted to prevent, mitigate or adapt to the implications of climate change. These regulations, which can differ across jurisdictions, subject Gilead to many transitional risks, including, for example, new or expanded carbon pricing or taxes, increased compliance costs, restrictions on greenhouse gas emissions, investment in new technologies, increased carbon disclosure and transparency, investments in data gathering and reporting systems, upgrades of facilities to meet new building codes and the redesign of utility systems, which could increase the company’s operating costs, including the cost of electricity and energy. Our suppliers and third-party manufacturers and corporate partners face similar transition risks and may pass along any increased costs to the company. 27 27 27

We are required to demonstrate the safety and efficacy of product candidates that we develop for each intended use through extensive preclinical studies and clinical trials. The results from these studies do not always accurately predict results in later, large-scale clinical trials. Even successfully completed large-scale clinical trials may not result in marketable products. We face numerous risks and uncertainties with our clinical trials that could result in delays or prevent completion of the development and approval of our product candidates, including challenges in clinical trial protocol design, our ability to enroll patients in clinical trials, the possibility of unfavorable or inadequate trial results to support further development of our product candidates, including failure to meet a trial’s primary endpoint, safety issues arising from our clinical trials, and the need to modify or delay our clinical trials or to perform additional trials. For example, in January 2024, we announced that our Phase 3 EVOKE-01 study evaluating sacituzumab govitecan-hziy did not meet its primary endpoint of overall survival in previously treated metastatic non-small cell lung cancer (“NSCLC”), which resulted in us recording an impairment charge during the three months ended March 31, 2024. In September 2024, we decided to discontinue our clinical development program in NSCLC for the second-line indication, resulting in us recording an impairment charge during the three months ended September 30, 2024 (for more information, see Note 9. Goodwill and Intangible Assets of the Notes to Consolidated Financial Statements included in Part II, Item 8 of this Annual Report on Form 10-K). In May 2024, we provided an update that (i) our Phase 3 TROPiCs-04 study did not meet its primary endpoint, which was a confirmatory study required in connection with the accelerated approval of sacituzumab govitecan-hziy for treatment of metastatic urothelial cancer, and (ii) there was a higher number of deaths due to adverse events with sacituzumab govitecan-hziy compared to treatment of physician’s choice. In addition, following results and data from several magrolimab studies as well as corresponding FDA clinical holds, we announced in February 2024 that we would not pursue further development of magrolimab in hematologic cancers. 21 21 21 As a result, we may be unable to successfully complete our clinical trials on our anticipated timelines, or at all. Based on trial results, it is possible that FDA and other regulatory authorities do not approve our product candidates, or that any market approvals include significant limitations on the products’ use. Additionally, products and indications approved under accelerated approval pathways may be subject to withdrawal where confirmatory studies are unsuccessful. In October 2024, we announced plans to voluntarily withdraw the U.S. accelerated approval for Trodelvy (sacituzumab govitecan-hziy; SG) for treatment of adult patients with locally advanced or metastatic urothelial cancer who have previously received a platinum-containing chemotherapy and either programmed death receptor-1 (PD-1) or programmed death-ligand 1 (PD-L1) inhibitor. In addition, clinical trials involving our commercial products can raise new safety issues for our existing products, which could adversely impact our business. Further, we have in the past and we may in the future make a strategic decision to discontinue development of our product candidates, including but not limited to situations where we believe commercialization will be difficult relative to other opportunities in our pipeline. For example, in January 2024, we announced with our partner Arcus Biosciences, Inc. (“Arcus”) the discontinuation of further enrollment in the Phase 3 ARC-10 study evaluating domvanalimab plus zimberelimab in first-line locally advanced or metastatic, PD-L1-high NSCLC based on strategic prioritization to advance and potentially accelerate other Phase 3 studies in our collaboration with Arcus. Therefore, our product candidates may never be successfully commercialized, and we may be unable to recoup the significant R&D, clinical trial, acquisition-related and other expenses incurred. We expect to spend significant time and resources on our clinical trial activities without any assurance that we will recoup our investments or that our efforts will be commercially successful. There are also risks associated with the use of third parties in our clinical trial activities. We extensively outsource our clinical trial activities and usually perform only a small portion of the start-up activities in-house. We rely on third-party contract research organizations (“CROs”) to perform most of our clinical studies, including document preparation, site identification, screening and preparation, pre-study visits, training, program management, patient enrollment, ongoing monitoring, site management and bioanalysis. Many important aspects of the services performed for us by the CROs are not within our direct control. If there is any dispute or disruption in our relationships with our CROs, including as a result of legislative or regulatory actions, our clinical trials and regulatory submissions may be delayed and our costs may increase. Moreover, in our regulatory submissions, we rely on the quality and validity of the clinical work performed by our CROs. If any of their processes, methodologies or results were determined to be invalid or inadequate, our own clinical data and results and related regulatory approvals may be adversely affected.

We are required to demonstrate the safety and efficacy of product candidates that we develop for each intended use through extensive preclinical studies and clinical trials. The results from these studies do not always accurately predict results in later, large-scale clinical trials. Even successfully completed large-scale clinical trials may not result in marketable products. 21 21 21 We face numerous risks and uncertainties with our clinical trials that could result in delays or prevent completion of the development and approval of our product candidates, including challenges in clinical trial protocol design, our ability to enroll patients in clinical trials, the possibility of unfavorable or inadequate trial results to support further development of our product candidates, including failure to meet a trial’s primary endpoint, safety issues arising from our clinical trials, and the need to modify or delay our clinical trials or to perform additional trials. For example, in October 2022, we announced that FDA issued a complete response letter for our Biologics License Application for bulevirtide for the treatment of adults with hepatitis delta virus infection. In January 2024, we announced that our Phase 3 EVOKE-01 study evaluating sacituzumab govitecan-hziy did not meet its primary endpoint of overall survival in previously treated metastatic non-small cell lung cancer (“NSCLC”). We believe that this represents an indicator of potential impairment in the first quarter of 2024, which could result in us being required to record an impairment charge during the three months ended March 31, 2024. Any such impairment charge, which we are unable to reasonably estimate at this time, could have a material impact on our results of operations (for more information, see Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations “Results of Operations - In-Process Research and Development Impairments”). In addition, in February 2024, we announced a full clinical hold placed by FDA on all magrolimab studies in myelodysplastic syndromes and acute myeloid leukemia, and that we will not pursue further development of magrolimab in hematologic cancers. As a result, we may be unable to successfully complete our clinical trials on our anticipated timelines, or at all. Based on trial results, it is possible that FDA and other regulatory authorities do not approve our product candidates, or that any market approvals include significant limitations on the products’ use. In addition, clinical trials involving our commercial products can raise new safety issues for our existing products, which could adversely impact our business. Further, we have in the past and we may in the future make a strategic decision to discontinue development of our product candidates, including but not limited to situations where we believe commercialization will be difficult relative to other opportunities in our pipeline. For example, in February 2024, we announced a full clinical hold placed by FDA on all magrolimab studies in myelodysplastic syndromes and acute myeloid leukemia, and based on these results and data from other clinical studies, we will not pursue further development of magrolimab in hematologic cancers. In addition, in January 2024, we announced with our partner Arcus Biosciences, Inc. (“Arcus”) the discontinuation of further enrollment in the Phase 3 ARC-10 study evaluating domvanalimab plus zimberelimab in first-line locally advanced or metastatic, PD-L1-high NSCLC based on strategic prioritization to advance and potentially accelerate other Phase 3 studies in our collaboration with Arcus. Therefore, our product candidates may never be successfully commercialized, and we may be unable to recoup the significant R&D and clinical trial expenses incurred. We expect to spend significant time and resources on our clinical trial activities without any assurance that we will recoup our investments or that our efforts will be commercially successful. There are also risks associated with the use of third parties in our clinical trial activities. We extensively outsource our clinical trial activities and usually perform only a small portion of the start-up activities in-house. We rely on independent third-party contract research organizations (“CROs”) to perform most of our clinical studies, including document preparation, site identification, screening and preparation, pre-study visits, training, program management, patient enrollment, ongoing monitoring, site management and bioanalysis. Many important aspects of the services performed for us by the CROs are out of our direct control. If there is any dispute or disruption in our relationship with our CROs, our clinical trials may be delayed. Moreover, in our regulatory submissions, we rely on the quality and validity of the clinical work performed by third-party CROs. If any of our CROs’ processes, methodologies or results were determined to be invalid or inadequate, our own clinical data and results and related regulatory approvals may be adversely affected.

If we are unable to launch commercially successful new products or new indications for existing products, including approval for earlier lines of therapy, our business will be adversely impacted. The launch of commercially successful products is necessary to grow our business, cover our substantial R&D expenses, and offset revenue losses when existing products lose market share due to factors such as competition and loss of patent exclusivity. There are many difficulties and uncertainties inherent in drug development and the introduction of new products. The product development cycle is characterized by significant investments of resources, long lead times and unpredictable outcomes due to the nature of developing medicines for human use. We expend significant time and resources on our product pipeline as well as on preparations for potential commercial launch without any assurance that we will recoup our investments or that our efforts will be commercially successful. A high rate of failure is inherent in the discovery and development of new products, and failure can occur at any point in the process, including late in the process after substantial investment. Such failures have had, and may have in the future, a negative impact on our business and financial results, including as a result of our inability to recover R&D, clinical trial, acquisition-related and other expenses incurred in connection with the development of and launch preparations for our product candidates. For example, we enter into commitments to purchase materials and supplies in anticipation of the potential manufacture and sale of new product candidates, and in the event the development, approval or launch of these product candidates is delayed or otherwise unsuccessful, we may experience excess inventory that needs to be written down, losses on firm commitments to purchase inventory, or other costs and expenses resulting from such commitments.

If we are unable to launch commercially successful new products or new indications for existing products, our business will be adversely impacted. The launch of commercially successful products is necessary to grow our business, cover our substantial R&D expenses, and offset revenue losses when existing products lose market share due to factors such as competition and loss of patent exclusivity. There are many difficulties and uncertainties inherent in drug development and the introduction of new products. The product development cycle is characterized by significant investments of resources, long lead times and unpredictable outcomes due to the nature of developing medicines for human use. We expend significant time and resources on our product pipeline without any assurance that we will recoup our investments or that our efforts will be commercially successful. A high rate of failure is inherent in the discovery and development of new products, and failure can occur at any point in the process, including late in the process after substantial investment.

The products we develop must be approved for marketing and sale by regulatory authorities and, once approved, are subject to extensive regulation by FDA, EMA and comparable regulatory agencies in other countries. We have filed, and anticipate that we will continue to file, for marketing approval in additional countries and for additional indications and products. These and any future marketing applications we file may not be approved by the regulatory authorities on a timely basis, or at all. For example, in October 2022, we announced that FDA issued a complete response letter for our Biologics License Application for bulevirtide for the treatment of adults with hepatitis delta virus infection. Even if marketing approval is granted for our product candidates, there may be significant limitations on their use. We cannot state with certainty when or whether any of our product candidates under development will be approved or launched; whether we will be able to develop, license or acquire additional product candidates or products; or whether any products, once launched, will be commercially successful. Further, how we manufacture and sell our products is subject to extensive regulation and review. For example, under FDA rules, we are often required to conduct post-approval clinical studies to assess a known serious risk, signals of serious risk or to identify an unexpected serious risk. In certain circumstances, we may be required to implement a Risk Evaluation and Mitigation Strategy program for our products, which could include a medication guide, patient package insert, a communication plan to healthcare providers, restrictions on distribution or use of a product and other elements FDA deems necessary to assure safe use of the drug. Discovery of previously unknown problems with our marketed products or product candidates, including serious safety, resistance or drug interaction issues, or problems with our manufacturing, safety reporting or promotional activities, may result in regulatory approvals being delayed, denied or granted with significant restrictions on our products, including limitations on or the withdrawal of the products from the market. As additional studies are conducted after obtaining marketing approval for our products, and as our products are used over longer periods of time by many patients, including patients with underlying health problems or those taking other medicines, we expect to continue finding new issues related to safety, resistance or drug interactions. Any such issues may require changes to our product labels, such as additional warnings, contraindications or even narrowed indications, or the halt of product sales. Regulatory authorities have been moving towards more active and transparent pharmacovigilance and are making greater amounts of stand-alone safety information and clinical trial data directly available to the public through websites and other means, such as periodic safety update report summaries, risk management plan summaries and various adverse event data. Safety information, without the appropriate context and expertise, may be misinterpreted and lead to misperception or legal action. Failure to comply with these or other requirements imposed by FDA could result in significant civil monetary penalties, fines, suspensions of regulatory approvals, product recalls, seizure of products and criminal prosecutions. 23 23 23

The products we develop must be approved for marketing and sale by regulatory authorities and, once approved, are subject to extensive regulation by FDA, EMA and comparable regulatory agencies in other countries. We have filed, and anticipate that we will continue to file, for marketing approval in additional countries and for additional indications and products. These and any future marketing applications we file may not be approved by the regulatory authorities on a timely basis, or at all. Even if marketing approval is granted for these products, there may be significant limitations on their use. We cannot state with certainty when or whether any of our product candidates under development will be approved or launched; whether we will be able to develop, license or acquire additional product candidates or products; or whether any products, once launched, will be commercially successful. Further, how we manufacture and sell our products is subject to extensive regulation and review. For example, under FDA rules, we are often required to conduct post-approval clinical studies to assess a known serious risk, signals of serious risk or to identify an unexpected serious risk. In certain circumstances, we may be required to implement a Risk Evaluation and Mitigation Strategy program for our products, which could include a medication guide, patient package insert, a communication plan to healthcare providers, restrictions on distribution or use of a product and other elements FDA deems necessary to assure safe use of the drug. Discovery of previously unknown problems with our marketed products or product candidates, including serious safety, resistance or drug interaction issues, or problems with our manufacturing, safety reporting or promotional activities, may result in regulatory approvals being delayed, denied or granted with significant restrictions on our products, including limitations on or the withdrawal of the products from the market. Failure to comply with these or other requirements imposed by FDA could result in significant civil monetary penalties, fines, suspensions of regulatory approvals, product recalls, seizure of products and criminal prosecutions.

We have engaged in, and may in the future engage in, such transactions as part of our business strategy. We may not identify suitable transactions in the future and, if we do, we may not complete such transactions in a timely manner, on a cost-effective basis, or at all, including the possibility that a governmental entity or regulatory body may delay or refuse to grant approval for the consummation of the transaction. If we are successful in making an acquisition or closing a licensing arrangement or collaboration, the products, intellectual property and technologies that are acquired or licensed may not be successful or may require significantly greater resources and investments than anticipated. As required by U.S. generally accepted accounting principles, we conduct annual impairment testing of our goodwill and other indefinite-lived intangible assets in the fourth quarter or more frequently if events or changes in circumstances indicate that it is more likely than not that the assets are impaired. We have in the past and may in the future need to recognize impairment charges related to the products, intellectual property and technologies that are acquired or licensed as a result of such testing. For example, we recorded partial impairment charges during the three months ended March 31, 2024 in connection with our Phase 3 EVOKE-01 study evaluating sacituzumab govitecan-hziy and during the three months ended September 30, 2024 following the strategic decision to discontinue our clinical development program in metastatic NSCLC for Trodelvy in the second-line indication (for more information, see Note 9. Goodwill and Intangible Assets of the Notes to Consolidated Financial Statements included in Part II, Item 8 of this Annual Report on Form 10-K). We also continue to monitor the progression of our in-process research and development assets related to sacituzumab govitecan-hziy for non-small cell lung cancer and bulevirtide for chronic hepatitis D virus for treatment primarily in the U.S. and may need to evaluate these items for impairment prior to the fourth quarter if there are any events or circumstances in our ongoing development activities indicating it is more like than not that these assets might be impaired. For option structured deals, there is no assurance that we will elect to exercise our option right, and it is possible that disagreements, uncertainties or other circumstances may arise, including with respect to whether our option rights have been appropriately triggered, which may hinder our ability to realize the expected benefits. For equity investments in our strategic partners, such as in connection with our collaborations with Arcus, Galapagos NV and Arcellx, Inc., the value of our equity investments may fluctuate and decline in value. If we are not successful in the execution or implementation of these transactions, our financial condition, cash flows and results of operations may be adversely affected, and our stock price could decline. We have paid substantial amounts of cash and incurred additional debt to finance our strategic transactions. Additional indebtedness and a lower cash balance could result in a downgrade of our credit ratings, limit our ability to borrow additional funds or refinance existing debt on favorable terms, increase our vulnerability to adverse economic or industry conditions, and reduce our financial flexibility to continue with our capital investments, stock repurchases and dividend payments. We may be adversely impacted by any failure to overcome these additional risks.

We have engaged in, and may in the future engage in, such transactions as part of our business strategy. We may not identify suitable transactions in the future and, if we do, we may not complete such transactions in a timely manner, on a cost-effective basis, or at all, including the possibility that a governmental entity or regulatory body may delay or refuse to grant approval for the consummation of the transaction. If we are successful in making an acquisition or closing a licensing arrangement or collaboration, the products, intellectual property and technologies that are acquired or licensed may not be successful or may require significantly greater resources and investments than anticipated. As part of our annual impairment testing of our goodwill and other indefinite-lived intangible assets in the fourth quarter, and earlier if impairment indicators exist, as required under U.S. generally accepted accounting principles, we have in the past and may in the future need to recognize impairment charges related to the products, intellectual property and technologies that are acquired or licensed. For example, as a result of an impairment analysis we conducted following our receipt of data in March 2022 from the Phase 3 TROPiCS-02 study evaluating Trodelvy in patients with hormone receptor-positive, human epidermal growth receptor 2-negative metastatic breast cancer, we recognized a partial in-process research and development impairment charge on our Condensed Consolidated Statements of Income during 2022. Similarly, we are evaluating whether we could be required to record an impairment charge during the three months ended March 31, 2024 in connection with our Phase 3 EVOKE-01 study evaluating sacituzumab govitecan-hziy. Any such impairment charge, which we are unable to reasonably estimate at this time, could have a material impact on our results of operations (for more information, see Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations “Results of Operations - In-Process Research and Development Impairments”). For option structured deals, there is no assurance that we will elect to exercise our option right, and it is possible that disagreements, uncertainties or other circumstances may arise, including with respect to whether our option rights have been appropriately triggered, which may hinder our ability to realize the expected benefits. For example, in March 2023, we waived our exclusive option to acquire Pionyr Immunotherapeutics, and in September 2023, we waived our exclusive option to acquire Tizona Therapeutics, Inc. For equity investments in our strategic partners, such as in connection with our collaborations with Arcus Biosciences, Inc. and Galapagos NV, the value of our equity investments may fluctuate and decline in value. If we are not successful in the execution or implementation of these transactions, our financial condition, cash flows and results of operations may be adversely affected, and our stock price could decline. We have paid substantial amounts of cash and incurred additional debt to finance our strategic transactions. Additional indebtedness and a lower cash balance could result in a downgrade of our credit ratings, limit our ability to borrow additional funds or refinance existing debt on favorable terms, increase our vulnerability to adverse economic or industry conditions, and reduce our financial flexibility to continue with our capital investments, stock repurchases and dividend payments. For example, as a result of the cash used and the debt issued in connection with our acquisition of Immunomedics, Inc. in 2020, S&P Global Ratings downgraded our credit rating. We may be adversely impacted by any failure to overcome these additional risks. 30 30 30

We need access to certain materials and supplies to conduct our clinical trials and to manufacture and sell our products. If we are unable to purchase enough of these materials and supplies or find suitable alternatives in a timely manner, our development efforts for our product candidates may be delayed or our ability to manufacture and sell our products could be limited. For example, in the U.S., there have been ongoing or recent shortages of certain cancer drugs that are the backbone of standard-of-care treatments, such as carboplatin and cisplatin, which are also used in R&D and clinical trials. While we have observed minimal impacts to our oncology clinical trials to date, if these shortages continue or increase in magnitude, our ongoing and future oncology clinical trials may be delayed, halted or adversely impacted. Suppliers of key components and materials must be named in the new drug application or marketing authorization application filed with the regulatory authority for any product candidate for which we are seeking marketing approval, and significant delays can occur if the qualification of a new supplier is required. Our products, which are manufactured at our own facilities or by third-party contract manufacturing organizations (“CMOs”) and corporate partners, are the result of complex, highly regulated manufacturing processes. We depend on CMOs and corporate partners to perform manufacturing activities effectively and on a timely basis for the majority of our active pharmaceutical ingredients and drug products. These third parties are independent entities subject to their own unique operational and financial risks that are out of our control. Some of our products and the materials that we utilize in our operations are manufactured by only one supplier or at only one facility, which we may not be able to replace in a timely manner and on commercially reasonable terms, or at all. We and our CMOs and corporate partners are subject to current Good Manufacturing Practices (“cGMP”), which are extensive regulations governing manufacturing processes, stability testing, recordkeeping and quality standards as defined by FDA and European Medicines Agency (“EMA”), as well as comparable regulations in other jurisdictions. Manufacturing operations are also subject to routine inspections by regulatory agencies. Even after a supplier is qualified by the regulatory authority, the supplier must continue to expend time, money and effort in the area of production and quality control to maintain full compliance with cGMP. If, as a result of these inspections, a regulatory authority determines that the equipment, facilities, laboratories or processes do not comply with applicable regulations and conditions of product approval, the regulatory authority may suspend the manufacturing operations. There can be no assurance that we will be able to remedy any deficiencies cited by FDA or other regulatory agencies in their inspections. Further, there is risk that regulatory agencies in other countries where marketing applications are pending will undertake similar additional reviews or apply a heightened standard of review, which could delay the regulatory approvals for products in those countries. 22 22 22 Any adverse developments affecting or resulting from any single entity within our manufacturing operations or the operations of our CMOs and corporate partners can result in shipment delays, inventory shortages, lot failures, product withdrawals or recalls or other interruptions in the development and commercial supply of our products, which may result in us not being able to generate sufficient quantities of clinical or commercial product to meet market demand and may cause delays in our clinical trials and applications for regulatory approval. We have incurred, and will continue to incur, inventory write-off charges and other expenses for products that fail to meet specifications and quality standards as well as changes we may adopt in our manufacturing strategy, and we may need to undertake costly remediation efforts or seek more costly manufacturing alternatives. Such developments could increase our manufacturing costs, cause us to lose revenues or market share and damage our reputation. Our business may be adversely affected if approval of any of our product candidates were delayed or if production of our products were interrupted.

We need access to certain supplies and products to conduct our clinical trials and to manufacture and sell our products. If we are unable to purchase enough of these materials or find suitable alternative materials in a timely manner, our development efforts for our product candidates may be delayed or our ability to manufacture and sell our products could be limited. For example, in the U.S., there has been a shortage of certain cancer drugs that are the backbone of standard-of-care treatments, such as carboplatin and cisplatin, which are also used in R&D and clinical trials. While we have observed minimal impacts to our oncology clinical trials to date, if these shortages continue or increase in magnitude, our ongoing and future oncology clinical trials may be delayed, halted or adversely impacted. Suppliers of key components and materials must be named in the new drug application or marketing authorization application filed with the regulatory authority for any product candidate for which we are seeking marketing approval, and significant delays can occur if the qualification of a new supplier is required. Even after a manufacturer is qualified by the regulatory authority, the manufacturer must continue to expend time, money and effort in the area of production and quality control to maintain full compliance with GMP. Manufacturers are subject to regular periodic inspections by regulatory authorities following initial approval. If, as a result of these inspections, a regulatory authority determines that the equipment, facilities, laboratories or processes do not comply with applicable regulations and conditions of product approval, the regulatory authority may suspend the manufacturing operations. If the manufacturing operations of any of the single suppliers for our products are suspended, we may be unable to generate sufficient quantities of commercial or clinical supplies of product to meet market demand. In addition, if deliveries of materials from our suppliers are interrupted for any reason, including as a result of natural disasters or extreme weather conditions, we may be unable to ship certain of our products for commercial supply or to supply our product candidates in development for clinical trials. Also, some of our products and the materials that we utilize in our operations are manufactured by only one supplier or at only one facility, which we may not be able to replace in a timely manner and on commercially reasonable terms, or at all. Problems with any of the single suppliers or facilities we depend on, including in the event of a disaster, such as an earthquake, flood or fire, equipment failure or other difficulty, may negatively impact our development and commercialization efforts. A significant portion of the raw materials and intermediates used to manufacture our antiviral products are supplied by third-party manufacturers and corporate partners outside of the U.S. As a result, any political or economic factors in a specific country or region, including any changes in or interpretations of trade regulations, compliance requirements or tax legislation, that would limit or prevent third parties outside of the U.S. from supplying these materials could adversely affect our ability to manufacture and supply our antiviral products to meet market needs and have a material and adverse effect on our operating results. If we were to encounter any of these difficulties, our ability to conduct clinical trials on product candidates and to manufacture and sell our products could be impaired. 23 23 23