Gilead Sciences, Inc. (Nasdaq: NASDAQ:GILD) today announced longer-term overall survival (OS) results from the Phase 3 TROPiCS-02 study evaluating Trodelvy® (sacituzumab govitecan-hziy) versus comparator chemotherapy (physicians’ choice of chemotherapy, TPC) in patients with HR+/HER2- (IHC0, IHC1+, IHC2+/ISH-) metastatic breast cancer who received endocrine-based therapies and at least two chemotherapies. In this exploratory analysis, Trodelvy demonstrated a clinically meaningful improvement in median OS benefit compared to TPC (median OS: 14.5 months vs. 11.2 months; hazard ratio (HR): 0.79; [95% CI: 0.65-0.95]; nominal p=0.0133). These findings will be shared as an oral presentation at the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract #1003). This abstract has also been selected to be included in the 2023 Best of ASCO® program, which will be held this summer following the ASCO Annual Meeting.
“These longer-term results show the durable overall survival benefit of sacituzumab govitecan over traditional chemotherapy in pre-treated HR+/HER2- metastatic breast cancer,” said Sara Tolaney, MD, MPH, Chief of the Division of Breast Oncology at the Dana-Farber Cancer Institute, and Associate Professor of Medicine, Harvard Medical School. “At this stage of disease, sequential chemotherapy is common, and benefits may become smaller with subsequent lines of therapy. The potential for a novel agent that may allow patients to live longer is especially meaningful.”
Progression-free survival (PFS) rates for Trodelvy vs. TPC were consistently higher at landmark milestones of 6, 12 and 18 months (45.6% vs. 29.4%, 21.7% vs. 8.4% and 14.4 vs. 4.7%, respectively). Similarly, OS rates for Trodelvy vs. TPC were consistently higher at landmark milestones of 12, 18, and 24 months (60.9% vs. 47.1%, 39.2% vs. 31.7%, and 25.7% vs. 21.1%, respectively). Ninety-two percent of patients in TROPiCS-02 were also eligible for evaluation of OS by HER2 status, as measured by immunohistochemistry (HER2 IHC0, n=217; HER2-low, n=283). Patients treated with Trodelvy demonstrated improved OS versus TPC in both the HER2 IHC0 (median OS: 13.6 months vs. 10.8 months; HR: 0.85 [95% CI: 0.63-1.14]) and HER2-low groups (median OS: 15.4 vs. 11.5 months; HR: 0.75 [95% CI: 0.57-0.97]).
“With these longer-term results in pre-treated HR+/HER2- metastatic breast cancer, Trodelvy has demonstrated proven survival benefit for patients who have had few options until now,” said Bill Grossman, MD, PhD, Senior Vice President, Therapeutic Area Head, Gilead Oncology. “We believe Trodelvy has the potential to transform outcomes for women across many different types of breast cancers. The survival benefit demonstrated for patients with pre-treated metastatic HR+/HER2- and metastatic triple-negative breast cancer are just the beginning of our clinical development journey. Our ambition is to extend this benefit to more patients, earlier in their treatment journey, where the potential impact is greatest.”
In TROPiCS-02, the most common grade ≥3 treatment emergent adverse events were neutropenia (52%), diarrhea (10%) and fatigue (6%) in the Trodelvy arm, and neutropenia (39%), thrombocytopenia (4%), fatigue (4%) and dyspnea (4%) for those treated with TPC. No new safety signals were identified. No patients treated with Trodelvy in TROPiCS-02 experienced interstitial lung disease (ILD). Trodelvy has a well-characterized safety profile consistent with that in previous studies. In the TROPiCS-02 study, the discontinuation rate due to adverse reactions was 6% for Trodelvy and 4% for patients on single-agent chemotherapy.
Trodelvy was approved in February 2023 by the U.S. Food and Drug Administration for the treatment of adult patients with unresectable locally advanced or metastatic HR+/HER2- breast cancer who have received endocrine-based therapy and at least two additional systemic therapies in the metastatic setting. The European Medicines Agency has also validated a Type II Variation Marketing Authorization Application for Trodelvy in HR+/HER2- metastatic breast cancer.
Trodelvy is also recommended as a Category 1, preferred treatment for metastatic HR+/HER2- breast cancer by the National Comprehensive Cancer Network® (NCCN®) as defined in the Clinical Practice Guidelines in Oncology (NCCN Guidelines®).i
Trodelvy has a Boxed Warning for severe or life-threatening neutropenia and severe diarrhea; please see below for additional Important Safety Information.