– Patients Whose Disease Changed to Triple-Negative Had Similar Positive Outcomes to Overall Metastatic TNBC Population in ASCENT Study –

– Trodelvy Is the First Treatment to Demonstrate Survival Benefit in Metastatic TNBC –

FOSTER CITY, Calif.--(BUSINESS WIRE)-- Gilead Sciences, Inc. (Nasdaq: GILD) today announced new data from the Phase 3 ASCENT study evaluating Trodelvy® (sacituzumab govitecan-hziy) in patients with relapsed or refractory metastatic triple-negative breast cancer (TNBC) who received two or more prior systemic therapies, at least one of them for metastatic disease. In a retrospective subgroup analysis, Trodelvy improved progression-free survival (PFS), overall survival (OS) and objective response rate (ORR) compared with chemotherapy chosen by the patients’ physicians in patients who were not initially diagnosed with TNBC. The results were presented at the European Society of Medical Oncology (ESMO) Congress 2021 from September 16-21, 2021 (Poster #258P).

“In the metastatic stage of breast cancer, it is not uncommon for people to change from one subtype to another,” said Javier Cortés, MD, Head of the International Breast Cancer Center (IBCC), Madrid and Barcelona, Spain. “Roughly one-third of patients with TNBC in the ASCENT study were not originally diagnosed with TNBC, and they still experienced a survival benefit with Trodelvy compared with chemotherapy. For treating physicians, this reinforces Trodelvy’s efficacy in more complex patients.”

This analysis included 146 chemotherapy-eligible brain metastasis-negative patients with an original breast cancer diagnosis that was not TNBC, of which 70 received Trodelvy and 76 received physician’s choice of chemotherapy. Among these patients, Trodelvy improved median PFS compared with chemotherapy (4.6 months vs. 2.3 months; HR: 0.48; P=0.0004), median OS (12.4 months vs. 6.7 months; HR: 0.44; P1%) were neutropenia (7%), diarrhea (4%), and pneumonia (3%). SAR were reported in 27% of patients, and 5% discontinued therapy due to adverse reactions. The most common Grade 3-4 lab abnormalities (incidence ≥25%) in the ASCENT study were reduced neutrophils, leukocytes, and lymphocytes.

In the TROPHY study (IMMU-132-06), the most common adverse reactions (incidence ≥25%) were diarrhea, fatigue, neutropenia, nausea, any infection, alopecia, anemia, decreased appetite, constipation, vomiting, abdominal pain, and rash. The most frequent serious adverse reactions (SAR) (≥5%) were infection (18%), neutropenia (12%, including febrile neutropenia in 10%), acute kidney injury (6%), urinary tract infection (6%), and sepsis or bacteremia (5%). SAR were reported in 44% of patients, and 10% discontinued due to adverse reactions. The most common Grade 3-4 lab abnormalities (incidence ≥25%) in the TROPHY study were reduced neutrophils, leukocytes, and lymphocytes.

DRUG INTERACTIONS

UGT1A1 Inhibitors: 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. Avoid administering UGT1A1 inhibitors with Trodelvy.

UGT1A1Inducers: Exposure to SN-38 may be substantially reduced in patients concomitantly receiving UGT1A1 enzyme inducers. Avoid administering UGT1A1 inducers with Trodelvy.

Please see full Prescribing Information, including BOXED WARNING.

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 and cancer. Gilead operates in more than 35 countries worldwide, with headquarters in Foster City, California.

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 within currently anticipated timelines or at all, including those involving Trodelvy; the possibility of unfavorable results from ongoing or additional trials, including those involving Trodelvy; Gilead’s ability to receive regulatory approvals in a timely manner or at all, including additional regulatory approvals of Trodelvy for the treatment of metastatic TNBC, metastatic breast cancer, metastatic UC, metastatic non-small cell lung cancer and other solid tumors, and the risk that any such approvals may be subject to significant limitations on use; and any assumptions underlying any of the foregoing. These and other risks, uncertainties and other factors are described in detail in Gilead’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2021, 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. Investors are cautioned that any such forward-looking statements are not guarantees of future performance and involve risks and uncertainties and are 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.

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

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

For more information about Gilead, please visit the company’s website at www.gilead.com, follow Gilead on Twitter (@GileadSciences) or call Gilead Public Affairs at 1-800-GILEAD-5 or 1-650-574-3000.

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Jacquie Ross, Investors (650) 358-1054

Karley Ura, Media (416) 858-0537

Source: Gilead Sciences, Inc.