A Randomized, Multicenter, Double-Blind, Placebo-Controlled Phase III Study of the Efficacy and Safety of Trastuzumab Emtansine in Combination With Atezolizumab or Placebo in Patients With HER2-Positive and PD-L1-Positive Locally Advanced or Metastatic Breast Cancer Who Have Received Prior Trastuzumab- (+/- Pertuzumab) and Taxane-Based Therapy (KATE3)

MO42319

This study will evaluate the efficacy, safety and patient-reported outcomes of trastuzumab emtansine plus atezolizumab compared with trastuzumab emtansine plus placebo in participants with HER2-positive and PD-L1-positive LABC or MBC.Participants must have progressed either during or after prior trastuzumab- (+/- pertuzumab) and taxane-based therapy for LABC/MBC; or during (or within 6 months after completing) trastuzumab- (+/-pertuzumab) and taxane-based therapy in the neoadjuvant and/or adjuvant setting.

2021-06-07

2024-04-30

2024-04-30

Active (not recruiting)

Early phase I

96

Inclusion Criteria: * HER2+ and PD-L1+ locally advanced (LABC) or metastatic breast cancer (MBC) * Progression must have occurred during most recent treatment for LABC/MBC or during, or within 6 months after completing, neoadjuvant and/or adjuvant therapy * Prior treatment with trastuzumab (+/- pertuzumab) and taxane in the neoadjuvant and/or adjuvant, locally advanced, or metastatic setting * No more than two prior lines of therapy in the metastatic setting * Measurable disease per RESIST version 1.1 * Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1 * Life expectancy \>= 6 months * Adequate hematologic and end-organ function * For women of childbearing potential: agreement to remain abstinent or use contraception, and agreement to refrain from donating eggs * For men: agreement to remain abstinent or use contraceptive measures, and agreement to refrain from donating sperm Exclusion Criteria: * Prior treatment with trastuzumab emtansine in metastatic setting * History of exposure to cumulative doses of anthracyclines * Symptomatic or actively progressing central nervous system (CNS) metastases; asymptomatic CNS lesions ≤ 2cm without clinical requirement for local intervention or asymptomatic patients with treated CNS lesions are eligible * Current Grade \>= 3 peripheral neuropathy * Cardiopulmonary dysfunction * History of malignancy within 5 years prior to initiation of study treatment, with the exception of the cancer under investigation and malignancies with a negligible risk of metastasis or death * History of leptomeningeal disease * Active or history of autoimmune disease or immune deficiency * Active hepatitis B, hepatitis C and/or tuberculosis * Prior allogeneic stem cell or solid organ transplantation * Receipt of a live, attenuated vaccine within 4 weeks prior to initiation of study treatment, during treatment, or within 5 months following the last dose of study treatment * Pregnancy or lactation

{'studyType': 'INTERVENTIONAL', 'phases': ['PHASE3'], 'designInfo': {'allocation': 'RANDOMIZED', 'interventionModel': 'PARALLEL', 'primaryPurpose': 'TREATMENT', 'maskingInfo': {'masking': 'DOUBLE', 'whoMasked': ['PARTICIPANT', 'INVESTIGATOR']}}, 'enrollmentInfo': {'count': 96, 'type': 'ESTIMATED'}}

2024-04-16