GILEAD SCIENCES, INC.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

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OUR CORPORATE STRATEGY

Letter from Our Chairman and Chief Executive Officer

Dear Stockholders,

Thank you for investing in Gilead at this exciting and dynamic time for the company. In 2025, we made history with lenacapavir for HIV prevention and continued to advance the strongest pipeline in our nearly 40-year history. Our momentum continues to build after another year of consistent growth and commercial excellence, along with plans for significant launch activity and no major loss of exclusivity expected for the coming decade. All of this gives us an exceptionally strong foundation to deliver on our mission in 2026 and beyond.

The investments and choices we made over the past year through our transformation strategy have directly shaped this era of impact and growth for Gilead. We have extended our leadership in HIV, while also driving innovation across virology, oncology and inflammation.

Gilead’s HIV business is the strongest it has ever been. In 2025, we achieved record sales driven by Biktarvy, the most-prescribed HIV treatment, along with significant growth in HIV prevention. We have been extremely pleased with the launch of Yeztugo, the world’s first twice-yearly HIV prevention following FDA approval. With its unique potential to bend the curve of the HIV epidemic, Yeztugo is a transformative medicine that we expect to drive durable, steady and long-term growth in our HIV prevention business for years to come. With up to seven potential treatment and prevention launches by 2033, we are well positioned to extend our HIV leadership into the 2040s.

In oncology, we received positive data for Trodelvy in breast cancer and for anito-cel in multiple myeloma, positioning us for potential approvals in 2026. Both therapies would build on our track record of delivering transformative or potentially curative therapies for patients with the most aggressive forms of cancer. We also recently announced an agreement to acquire Arcellx, our partner on anito-cel since 2022. The agreement, which is subject to customary closing conditions, reflects our conviction in anito-cel’s potential as a best-class cell therapy with a differentiated safety profile, and our intention to bring that potential to patients as quickly as possible.

We continue to advance our portfolio of therapies for inflammation and liver diseases to support pipeline diversification and long-term growth. The launch of Livdelzi for primary biliary cholangitis has seen rapid adoption, and we could potentially see a U.S. launch of bulevirtide for chronic hepatitis delta in 2026.

All this progress reflects the success of our strategy, and we are excited by what’s to come. We anticipate a steady cadence of upcoming Phase 3 readouts and potential near-term launches ahead. Importantly, our financial position is robust, underpinned by a disciplined and proactive approach to expense management and business development. We remain focused on strong execution and growing long-term value for our shareholders.

As we enter 2026, and on behalf of the Gilead Board of Directors, thank you for being part of our progress and our work to create a healthier world for all people.

Sincerely,

Daniel O’Day

Chairman and Chief Executive Officer

Letter from Our Lead Independent Director

Dear Stockholders,

At Gilead, our vision remains clear: to create a healthier world for all people. In 2025, the company advanced pioneering work in virology, oncology and inflammation, delivering innovative therapies that offer new hope to those affected by serious diseases.

The Board of Directors plays a critical role in overseeing the company’s long-term strategy and supporting the best interests of our stockholders. This past year, the Board focused on Gilead’s efforts to strengthen our HIV leadership, build a differentiated oncology portfolio and drive long-term diversification, while also maintaining close attention to capital allocation, risk management and leadership development. Through disciplined oversight and efficient execution by management, Gilead exited 2025 in a robust position, supported by growth in our HIV business and Trodelvy franchise, multiple positive pivotal trial read-outs, the deepest pipeline in our history and a strong operating margin.

The Board also dedicated significant time to overseeing Gilead’s risk profile amid an increasingly complex external environment. Key areas that we believe have the significant potential to affect long-term value include portfolio decisions, competitive and regulatory developments, geopolitical uncertainty and evolving industry requirements. We also devoted time to the governance of emerging technologies, recognizing the transformative potential of artificial intelligence (AI) in our business and industry. Within this context, the Board oversaw the rollout of Gilead’s AI Principles in February 2025 and engaged in ongoing, detailed discussions with management on the responsible integration and use of AI across the business. We believe it is important that Gilead’s AI strategy incorporate appropriate controls, accountability and risk management.

As Lead Independent Director, my role is to empower the leadership of our independent directors and support effective oversight. I remain committed to fostering a collaborative and transparent partnership with executive management, while ensuring constructive challenge and independent judgment in Board deliberations. Through regular executive sessions of the independent directors, a comprehensive Board self-assessment process and candid conversations outside the boardroom, we continue to drive management accountability, provide strategic input and support disciplined decision-making that enhances performance and delivers sustainable, long-term value.

Engaging directly with our stockholders remains one of the most rewarding aspects of my role. In 2025, Gilead engaged with investors representing approximately 42% of our outstanding shares, and I had the pleasure of meeting with investors representing approximately 30% of our outstanding shares. The perspectives we heard—spanning business strategy, Board composition, corporate governance practices, executive compensation and corporate responsibility—meaningfully informed our deliberations and subsequent actions, reinforcing our commitment to transparency, accountability and alignment with stockholder interests.

Looking ahead, the Board is confident in Gilead’s strategic direction and leadership. Long-term success requires both strong performance today and thoughtful preparation for the future, grounded in robust oversight, sound governance and a focus on sustainable value creation.

On behalf of the Board, thank you for your continued trust, engagement and support. We look forward to our ongoing dialogue and to serving your interests in the year ahead.

Sincerely,

Anthony Welters

Lead Independent Director

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