– Trodelvy is a New Backbone Therapy and the Only Approved ADC in First-Line mTNBC Across PD-L1 Status –

– Approval Builds on Trodelvy’s Leadership in Second-Line mTNBC and Pre-Treated HR+/HER2- Metastatic Breast Cancer with More than 75,000 Patients Treated Globally –

Gilead Sciences, Inc. (NASDAQ:GILD) today announced that the U.S. Food and Drug Administration (FDA) has approved Trodelvy^® (sacituzumab govitecan-hziy), a first-in-class Trop-2-directed antibody-drug conjugate (ADC), for the first-line treatment of adult patients with unresectable locally advanced or metastatic triple-negative breast cancer (mTNBC). Trodelvy is now approved in first-line mTNBC either as a single agent for patients who are not candidates for PD-(L)1 inhibitor-based therapy or in combination with Keytruda^® (pembrolizumab) or Keytruda Qlex™ (pembrolizumab and berahyaluronidase alfa-mph) for patients whose tumors express PD-L1 (CPS ≥10) as determined by an FDA-authorized test.

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"For people living with mTNBC, the first treatment choice can be pivotal, as many patients may not have the opportunity to receive subsequent therapies," said Sara Tolaney, MD, MPH, Chief of the Division of Breast Oncology at Dana-Farber Cancer Institute and a principal investigator of the ASCENT-03 and ASCENT-04 studies. "This approval is heartening news for patients and the clinical community, and I believe offers a practice-changing first-line treatment option for all patients across PD-L1 status."

The FDA approval is based on highly statistically significant and clinically meaningful progression-free survival (PFS) data from the Phase 3 ASCENT-03 and ASCENT-04/KEYNOTE-D19 trials, where Trodelvy-based regimens significantly reduced the risk of disease progression or death in first-line mTNBC—by 38% as monotherapy versus chemotherapy in PD-L1 ineligible disease in ASCENT-03 and by 35% in combination with Keytruda versus Keytruda plus chemotherapy in PD-L1+ disease in ASCENT-04.

Across ASCENT-03 and ASCENT-04, Trodelvy-based regimens delivered markedly more durable responses, with median duration of response of 12.2 versus 7.2 months with chemotherapy in ASCENT-03 and 16.5 versus 9.2 months for Trodelvy plus Keytruda versus Keytruda plus chemotherapy in ASCENT-04 by blinded independent central review.

"For patients with metastatic TNBC, a new first-line treatment option offers optimism to a community with historically few choices," said Ricki Fairley, Co-Founder and CEO of TOUCH, The Black Breast Cancer Alliance. "TNBC disproportionately affects younger women - many in the prime of their lives - and often leads to poorer outcomes. Because so many patients may never receive subsequent lines of therapy, the ability to start with a promising option like Trodelvy with or without Keytruda is critical. We have sought additional alternatives to chemotherapy-containing regimens in the first-line metastatic setting since TNBC was classified as a disease more than 20 years ago. As such, this approval represents meaningful progress for the families impacted by this disease."

"The FDA’s approval of Trodelvy provides a new standard of care for the most aggressive form of breast cancer," said Dietmar Berger, MD, PhD, Chief Medical Officer, Gilead Sciences. "For more than twenty years, patients with mTNBC have had limited choices in first-line treatment. Building on its impact in second-line mTNBC, Trodelvy now offers patients a powerful new backbone therapy option in the first-line setting."

Based on the ASCENT-03 and ASCENT-04 positive study results, the National Comprehensive Cancer Network^® (NCCN^®) recommends Trodelvy with or without Keytruda as a category 1 preferred first-line treatment option for people with mTNBC across PD-L1 status in the NCCN Guidelines^®i. Trodelvy also has a category 1 recommendation in second-line mTNBC and in pre-treated HR+/HER2-negative (IHC 0, IHC 1+ or IHC 2+/ISH-) metastatic breast cancer (mBC).

Healthcare professionals have well-established experience with Trodelvy, with more than 75,000 breast cancer patients treated across more than 60 countries over the past six years. It remains the only Trop-2-directed ADC to demonstrate meaningful overall survival benefits in both second-line or later metastatic TNBC and pre-treated HR+/HER2- mBC. It is also the only ADC with four positive Phase 3 trials in HER2-negative (IHC 0, IHC 1+ or IHC 2+/ISH-) mBC.

Please see below for the U.S. Indication and Important Safety Information for Trodelvy, including Boxed Warning.

KEYTRUDA^® and KEYTRUDA QLEX™ are trademark(s) of Merck Sharp & Dohme LLC., a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.

About Triple-Negative Breast Cancer

TNBC is the most aggressive type of breast cancer and has historically been difficult to treat, accounting for approximately 15% of all breast cancers. TNBC disproportionally impacts younger, premenopausal, and Black and Hispanic women. TNBC cells do not have estrogen and progesterone receptors and have limited HER2 expression. Due to the nature of TNBC, treatment options are extremely limited compared with other breast cancer types. TNBC has a higher chance of recurrence and metastases than other breast cancer types. The average time to metastatic recurrence for TNBC is approximately 2.6 years compared with 5 years for other breast cancers, and the relative five-year survival rate is much lower. Among women with metastatic TNBC, the five-year survival rate is 12%, compared with 28% for those with other types of mBC.

First-line metastatic TNBC has seen limited new approvals in recent years and additional options are urgently needed. Over 50% of patients do not receive treatment beyond first-line, reinforcing the urgent need for new options to help improve patient outcomes. Breast cancers expressing PD-L1 are overall more aggressive and associated with reduced survival time.

About Trodelvy

Trodelvy (sacituzumab govitecan-hziy) is a first-in-class Trop-2-directed antibody-drug conjugate. Trop-2 is a cell surface antigen highly expressed in multiple tumor types, including in more than 90% of breast and lung cancers. Trodelvy is intentionally designed with a proprietary hydrolyzable linker attached to SN-38, a topoisomerase I inhibitor payload. This unique combination delivers potent activity to both Trop-2 expressing cells and the tumor microenvironment through a bystander effect.

Trodelvy is currently approved in more than 60 countries for second-line or later metastatic triple-negative breast cancer (TNBC) and in more than 50 countries for certain patients with pre-treated HR+/HER2- metastatic breast cancer (mBC). Global regulatory submissions for the approval of Trodelvy based on ASCENT-03 and ASCENT-04 are underway.

Trodelvy is currently being evaluated in multiple ongoing Phase 3 trials across a range of tumor types with high Trop-2 expression. These studies with Trodelvy, both in monotherapy and in combination with pembrolizumab, involve earlier lines of treatment for TNBC and HR+/HER2- breast cancer—including in curative settings—as well as in lung and gynecologic cancers, where previous proof-of-concept studies have demonstrated clinical activity.

INDICATIONS

TRODELVY^® (sacituzumab govitecan-hziy) is a Trop-2–directed antibody and topoisomerase inhibitor conjugate indicated in adult patients:

Locally Advanced or Metastatic Triple-Negative Breast Cancer

First Line

As a single agent for the first-line treatment of unresectable locally advanced or metastatic triple-negative breast cancer (mTNBC) who are not candidates for PD-1 or PD-L1 inhibitor-based therapy
In combination with pembrolizumab or pembrolizumab and berahyaluronidase alfa-pmph for the first-line treatment of unresectable locally advanced or mTNBC whose tumors express PD-L1 [Combined Positive Score (CPS ≥10)] as determined by an FDA-authorized test

Second Line or Later

For the treatment of unresectable locally advanced or mTNBC who have received two or more prior systemic therapies, at least one of them for metastatic disease.

Locally Advanced or Metastatic HR-positive, HER2-negative Breast Cancer

For the treatment of unresectable locally advanced or metastatic hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative (IHC 0, IHC 1+, or IHC 2+/ISH–) breast cancer who have received endocrine-based therapy and at least two additional systemic therapies in the metastatic setting.

IMPORTANT SAFETY INFORMATION

BOXED WARNING: NEUTROPENIA AND DIARRHEA

TRODELVY can cause severe, life-threatening, or fatal neutropenia. Withhold TRODELVY for absolute neutrophil count below 1500/mm³ or neutropenic fever. Monitor blood cell counts periodically during treatment. Primary prophylaxis with G-CSF is recommended for all patients at increased risk of febrile neutropenia. Initiate anti-infective treatment in patients with febrile neutropenia without delay.

TRODELVY can cause severe diarrhea. Monitor patients with diarrhea and give fluid and electrolytes as needed. At the onset of diarrhea, evaluate for infectious causes and, if negative, promptly initiate loperamide. If severe diarrhea occurs, withhold TRODELVY until resolved to ≤Grade 1 and reduce subsequent doses.

CONTRAINDICATIONS

Severe hypersensitivity reaction to TRODELVY.

WARNINGS AND PRECAUTIONS

Neutropenia: Severe, life-threatening, or fatal neutropenia can occur as early as the first cycle of treatment and may require dose modification. Neutropenia occurred in 64% of patients treated with TRODELVY. Grade 3-4 neutropenia occurred in 48% of patients. Febrile neutropenia occurred in 6%. Neutropenic colitis occurred in 1.4%. Primary prophylaxis with G-CSF is recommended starting in the first cycle of treatment in all patients at increased risk of febrile neutropenia, including older patients, patients with previous neutropenia, poor performance status, organ dysfunction, or multiple comorbidities. Monitor absolute neutrophil count (ANC) during treatment. Withhold TRODELVY for ANC below 1500/mm³ on Day 1 of any cycle or below 1000/mm³ on Day 8 of any cycle. Withhold TRODELVY for neutropenic fever. Treat neutropenia with G-CSF and administer prophylaxis in subsequent cycles as clinically indicated or indicated in Table 2 of USPI.

Diarrhea: Diarrhea occurred in 62% of all patients treated with TRODELVY. Grade 3-4 diarrhea occurred in 10% of patients. One patient had intestinal perforation following diarrhea. Diarrhea that led to dehydration and subsequent acute kidney injury occurred in 0.6% of all patients. Withhold TRODELVY for Grade 3-4 diarrhea and resume when resolved to ≤Grade 1. At onset, evaluate for infectious causes and, if negative, promptly initiate loperamide, 4 mg initially followed by 2 mg with every episode of diarrhea for a maximum of 16 mg daily. Discontinue loperamide 12 hours after diarrhea resolves. Additional supportive measures (eg, fluid and electrolyte replacement) may also be employed as clinically indicated. Patients who exhibit an excessive cholinergic response to treatment can receive appropriate premedication (eg, atropine) for subsequent treatments.

Hypersensitivity and Infusion-Related Reactions: TRODELVY can cause serious hypersensitivity reactions, including life-threatening anaphylactic reactions. Severe signs and symptoms included cardiac arrest, hypotension, wheezing, angioedema, swelling, and skin reactions. Hypersensitivity reactions occurred in 28% of patients with 13% occurring within 24 hours of dosage. Grade 3-4 hypersensitivity occurred in 1.5% of patients with 0.4% of these occurring within 24 hours of dosage. The incidence of hypersensitivity reactions leading to permanent discontinuation of TRODELVY was 0.4%. The incidence of anaphylactic reaction was <0.1%. Pre-infusion medication is recommended. Have medications and emergency equipment to treat such reactions available for immediate use. Closely monitor patients for hypersensitivity and infusion-related reactions during each infusion and for at least 30 minutes after completion of each infusion. Permanently discontinue TRODELVY for Grade 4 infusion-related reactions.

Nausea and Vomiting: TRODELVY is emetogenic and can cause severe nausea and vomiting. Nausea occurred in 63% of all patients treated with TRODELVY, and Grade 3-4 nausea occurred in 3% of these patients. Vomiting occurred in 33% of patients, and Grade 3-4 vomiting occurred in 2% of these patients. Premedicate with a two- or three-drug combination regimen (eg, dexamethasone with either a 5-HT3 receptor antagonist or an NK₁ receptor antagonist, as well as other drugs as indicated) for prevention of chemotherapy-induced nausea and vomiting. Withhold TRODELVY doses for Grade 3 nausea or Grade 3-4 vomiting and resume with additional supportive measures when resolved to ≤Grade 1. Additional antiemetics and other supportive measures may also be employed as clinically indicated. All patients should be given take-home medications with clear instructions for prevention and treatment of nausea and vomiting.

Increased Risk of Adverse Reactions in Patients With Reduced UGT1A1 Activity: Patients homozygous for the uridine diphosphate-glucuronosyl transferase 1A1 (UGT1A1)*28 allele are at increased risk for neutropenia, febrile neutropenia, and anemia and may be at increased risk for other adverse reactions with TRODELVY. The incidence of Grade 3-4 neutropenia was 57% in patients homozygous for the UGT1A1*28 allele, 48% in patients heterozygous for the UGT1A1*28 allele, and 41% in patients homozygous for the wild-type allele. The incidence of Grade 3-4 anemia was 17% in patients homozygous for the UGT1A1*28 allele, 9% in patients heterozygous for the UGT1A1*28 allele, and 8% in patients homozygous for the wild-type allele. Closely monitor patients with known reduced UGT1A1 activity for adverse reactions. Withhold or permanently discontinue TRODELVY based on clinical assessment of the onset, duration, and severity of the observed adverse reactions in patients with evidence of acute early-onset or unusually severe adverse reactions, which may indicate reduced UGT1A1 function.

Embryo-Fetal Toxicity: Based on its mechanism of action, TRODELVY can cause teratogenicity and/or embryo-fetal lethality when administered to a pregnant woman. TRODELVY contains a genotoxic component, SN-38, and targets rapidly dividing cells. Advise pregnant women and females of reproductive potential of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment with TRODELVY and for 6 months after the last dose. Advise male patients with female partners of reproductive potential to use effective contraception during treatment with TRODELVY and for 3 months after the last dose.

ADVERSE REACTIONS

In the pooled safety population of TRODELVY as a single agent, the most common (≥25%) adverse reactions, including laboratory abnormalities, were decreased leukocyte count (83%), decreased neutrophil count (77%), decreased hemoglobin (71%), nausea (63%), diarrhea (62%), decreased lymphocyte count (60%), fatigue (59%), alopecia (47%), increased glucose (40%), constipation (37%), vomiting (33%), decreased albumin (32%), increased alkaline phosphatase (30%), decreased appetite (28%), abdominal pain (27%), decreased creatinine clearance (27%), decreased magnesium and potassium (26% each).

In the safety population of TRODELVY in combination with pembrolizumab, the most common (≥25%) adverse reactions, including laboratory abnormalities, were decreased neutrophil count and hemoglobin (86% each), decreased leukocyte count (84%), diarrhea (72%), nausea (68%), decreased lymphocyte count (61%), fatigue (58%), alopecia (52%), increased alkaline phosphatase and glucose (50% each), increased alanine aminotransferase (47%), constipation (41%), increased aspartate aminotransferase (40%), rash (37%), decreased potassium (35%), increased lactate dehydrogenase (34%), vomiting (29%), abdominal pain, headache, and increased eosinophils (26% each), and decreased albumin (25%).

In the ASCENT-03 study (single agent in previously untreated, unresectable locally advanced or mTNBC), the most common adverse reactions (incidence ≥25%) were nausea, diarrhea, alopecia, fatigue, constipation, and vomiting. The most frequent serious adverse reactions (SAR) (>2%) were diarrhea, febrile neutropenia, and neutropenia (3.6% each), and pneumonia (2.9%). SAR occurred in 26% of patients, and 3.6% permanently discontinued TRODELVY due to adverse reactions. Fatal adverse reactions occurred in 2.5% of patients and included sepsis (1.1%), and acute respiratory failure, neutropenic colitis, pneumonia, and septic shock (0.4% each). The most common Grade 3-4 lab abnormalities (incidence ≥25%) were decreased neutrophils and leukocytes.

In the ASCENT-04 study (in combination with pembrolizumab in previously untreated, unresectable locally advanced or mTNBC whose tumors express PD-L1), the most common adverse reactions (incidence ≥25%) were diarrhea, nausea, fatigue, alopecia, constipation, rash, vomiting, abdominal pain, and headache. The most frequent SAR (≥2%) were febrile neutropenia (7%), neutropenia (6%), diarrhea (5%), and fatigue and pneumonia (2.3% each). SAR occurred in 38% of patients, and 7% permanently discontinued TRODELVY due to adverse reactions. Fatal adverse reactions occurred in 3.2% of patients and included death (unknown cause) (0.9%) and completed suicide, neutropenic sepsis, sepsis, pneumonia, and pulmonary embolism (0.5% each). The most common Grade 3-4 lab abnormalities (incidence ≥25%) were decreased neutrophils and leukocytes.

In the ASCENT study (previously treated locally advanced or mTNBC), the most common adverse reactions (incidence ≥25%) were fatigue, diarrhea, nausea, alopecia, constipation, vomiting, abdominal pain, and decreased appetite. The most frequent SAR (>1%) were neutropenia (7%), diarrhea (4%), and pneumonia (3%). SAR occurred in 27% of patients, and 5% permanently discontinued TRODELVY due to adverse reactions. Fatal adverse reactions occurred in 1.2% of patients and included respiratory failure (0.8%) and pneumonia (0.4%). The most common Grade 3-4 lab abnormalities (incidence ≥25%) were decreased neutrophils, leukocytes, and lymphocytes.

In the TROPiCS-02 study (locally advanced or metastatic HR+/HER2– breast cancer), the most common adverse reactions (incidence ≥25%) were diarrhea, fatigue, nausea, alopecia, and constipation. The most frequent SAR (>1%) were diarrhea (5%), febrile neutropenia (4.1%), neutropenia (3%), abdominal pain (2.2%), neutropenic colitis and vomiting (1.9% each), and colitis and pneumonia (1.5% each). SAR occurred in 28% of patients, and 6% permanently discontinued TRODELVY due to adverse reactions. Fatal adverse reactions occurred in 2.2% of patients and included arrhythmia, COVID-19 pneumonia, pneumonia, nervous system disorder, pulmonary embolism, and septic shock (0.4% each). The most common Grade 3-4 lab abnormalities (incidence ≥25%) were decreased neutrophils and leukocytes.

DRUG INTERACTIONS

UGT1A1 Inhibitors: Avoid administering UGT1A1 inhibitors with TRODELVY. SN-38 is a UGT1A1 substrate. Concomitant administration of TRODELVY with inhibitors of UGT1A1 may increase the incidence of adverse reactions due to potential increase in systemic exposure to SN-38.

UGT1A1 Inducers: Avoid administering UGT1A1 inducers with TRODELVY. SN-38 is a UGT1A1 substrate. Concomitant administration of TRODELVY with inducers of UGT1A1 may reduce exposure to SN-38.

Please see full Prescribing Information, including BOXED WARNING.

About Gilead and Kite Oncology

Gilead and Kite Oncology are working to transform how cancer is treated. We are innovating with next-generation therapies, combinations and technologies to deliver improved outcomes for people with cancer. We are purposefully building our oncology portfolio and pipeline to address the greatest gaps in care. From antibody-drug conjugate technologies and small molecules to cell therapy-based approaches, we are creating new possibilities for people with cancer.

About Gilead Sciences

Gilead Sciences, Inc. is a biopharmaceutical company that has pursued and achieved breakthroughs in medicine for more than three decades, with the goal of creating a healthier world for all people. The company is committed to advancing innovative medicines to prevent and treat life-threatening diseases, including HIV, viral hepatitis, COVID-19, cancer and inflammation. In 2025, Gilead announced a planned $32 billion investment to further strengthen its U.S. footprint to power the next era of discovery, job creation and public health preparedness – while continuing to invest globally to ensure patients everywhere benefit from its scientific innovation. Gilead operates in more than 35 countries worldwide, with headquarters in Foster City, Calif.

Forward-Looking Statements

This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks, uncertainties and other factors, including Gilead’s ability to initiate, progress or complete clinical trials or studies within currently anticipated timelines or at all, and the possibility of unfavorable results from ongoing and additional clinical trials or studies, including those involving sacituzumab govitecan-hziy (such as ASCENT-03 and ASCENT-04); uncertainties relating to regulatory applications and related filing and approval timelines, including potential applications for programs and/or indications currently under evaluation, and the risk that any regulatory approvals, if granted, may be subject to significant limitations on use or subject to withdrawal or other adverse actions by the applicable regulatory authority; the possibility that Gilead may make a strategic decision to discontinue development of these programs and, as a result, these programs may never be successfully commercialized for the indications currently under evaluation; the risk that physicians and patients may not see advantages of Trodelvy for first-line mTNBC and may therefore be reluctant to prescribe the products; and any assumptions underlying any of the foregoing. These and other risks, uncertainties and factors are described in detail in Gilead’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2026, as filed with the U.S. Securities and Exchange Commission. These risks, uncertainties and other factors could cause actual results to differ materially from those referred to in the forward-looking statements. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. The reader is cautioned that any such forward-looking statements are not guarantees of future performance and involve risks and uncertainties and is cautioned not to place undue reliance on these forward-looking statements. All forward-looking statements are based on information currently available to Gilead, and Gilead assumes no obligation and disclaims any intent to update any such forward-looking statements.

Trodelvy, Gilead and the Gilead logo are trademarks of Gilead Sciences, Inc., or its related companies.

U.S. Prescribing Information for Trodelvy, including BOXED WARNING, is available at www.gilead.com.

For more information about Gilead, please visit the company’s website at www.gilead.com, follow Gilead on X/Twitter (@Gilead Sciences) and LinkedIn (@Gilead-Sciences).

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ⁱ Referenced with permission from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for Breast Cancer Version 4.2026. © National Comprehensive Cancer Network, Inc. 2026. All rights reserved. Accessed June 16, 2026. To view the most recent and complete version of the guideline, go online to NCCN.org. NCCN makes no warranties of any kind whatsoever regarding their content, use or application and disclaims any responsibility for their application or use in any way.

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Priscilla White, Media

Public_affairs@gilead.com

Jacquie Ross, Investors

Investor_relations@gilead.com

U.S. FDA Approves Trodelvy® for First-Line Treatment of Metastatic Triple-Negative Breast Cancer