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No longer recruiting (closed or complete)Last updated: 3 February 2025

KATE3: This Phase III trial is trying to understand the safety and effectiveness of targeted therapy (trastuzumab emtansine) in combination with immunotherapy (atezolizumab) in people with locally advanced or metastatic breast cancerA 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)

Trial purpose

Medical clipboardCancer treatment

Tumor type

Breast Cancers Breast

Age

People18+

Trial acronym

KATE3

Clinical summary

Summary

This is a double-blind, randomised parallel assignment trial with experimental and active comparator arms. Participants in the active comparator arm will receive a placebo, followed by 3.6 milligrams per kilogram (mg/kg) of intravenous (IV) trastuzumab emtansine. Participants in the Experimental arm will receive 1200 mg IV Atezolizumab followed by 3.6 mg/kg IV trastuzumab emtansine. All participants will receive the above treatments on Day 1, Cycle 1 and thereafter on Day 1 of each 21-day cycle until disease progression, unmanageable toxicity, or study termination by the sponsor.

Conditions

This trial is treating people with breast cancer

Eligibility

Inclusion

  • 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

  • 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

Inclusion

  • Your cancer has spread to other parts of the body (metastatic) or has grown into nearby parts of the body (locally advanced).
  • You have had treatment but your cancer has gotten worse or has not responded to the treatment you have been given.
  • You have had a certain type of treatment or surgical procedure.

Exclusion

  • You have certain types of non-cancer medical conditions.
  • You have had certain treatments, surgical procedures or drugs.
Message

Clinical trials have complex eligibility criteria, and other criteria may apply for this trial. Ask your doctor about whether this trial could be right for you.

Participating hospitals

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No longer recruiting (closed or complete) hospitals

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More information

Trial Identifiers

Information on this page is partially produced from ClinicalTrials.gov *. View further details about this trial on the registry via the links below:

Trial sponsor

Hoffmann-La Roche

Scientific Title

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)

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