Open Actively Recruiting

A Study Evaluating the Efficacy and Safety of Adjuvant Atezolizumab or Placebo and Trastuzumab Emtansine for Participants With HER2-Positive Breast Cancer at High Risk of Recurrence Following Preoperative Therapy


Brief Summary

This is a Phase III, two-arm, randomized, double-blind placebo-controlled study in participants with HER2-positive primary breast cancer who have received preoperative chemotherapy and HER2-directed therapy, including trastuzumab followed by surgery, with a finding of residual invasive disease in the breast and/or axillary lymph nodes.

Primary Purpose
Study Type
Phase 3


Healthy Volunteers
Minimum Age
18 Years
Maximum Age

Inclusion Criteria:

  • Histologically confirmed invasive breast carcinoma
  • Centrally-confirmed human epidermal growth factor receptor 2 (HER2)-positive invasive breast cancer
  • Centrally confirmed PD-L1 and hormone receptor status
  • Clinical stage at disease presentation (prior to neoadjuvant therapy): cT4/anyN/M0, any cT/N2-3/M0, or cT1-3/N0-1/M0 (participants with cT1mi/T1a/T1b/N0 are not eligible)
  • Completion of pre-operative systemic chemotherapy including at least 9 weeks of taxane and 9 weeks of trastuzumab (anthracycline and/or additional HER2-targeted agents are permitted)
  • <=12 weeks between primary surgery and randomization
  • Eastern Cooperative Oncology Group (ECOG) Performance Status 0 or 1
  • Screening left ventricular ejection fraction (LVEF) >= 50% and no decrease in LVEF by >15% from the pre-chemotherapy LVEF. If no pre-chemotherapy LVEF, screening LVEF >= 55%
  • Life expectancy >= 6 months
  • Adequate hematologic and end organ function

Exclusion Criteria:

  • Stage IV breast cancer
  • An overall response of disease progression according to the investigator at the conclusion of preoperative systemic therapy
  • Prior treatment with T-DM1, or atezolizumab, or other immune checkpoint inhibitors
  • History of exposure to various cumulative doses of anthracyclines
  • History of other malignancy within 5 years prior to screening, except for appropriately treated carcinoma in situ of the cervix, non-melanoma skin carcinoma, Stage I uterine cancer, or ductal carcinoma in situ (DCIS)
  • Current grade >=2 peripheral neuropathy
  • History of idiopathic pulmonary fibrosis, organizing pneumonia, or pneumonitis
  • History of or active autoimmune disease or immune deficiency
  • Treatment with immunostimulatory or immunosuppressive agents
  • Cardiopulmonary dysfunction
  • Any known active liver disease

Join this Trial

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Study Stats
Protocol No.
Breast Cancer
Monica Rocha
  • UCLA Alhambra
  • UCLA Beverly Hills
  • UCLA Burbank
  • UCLA Irvine
  • UCLA Laguna Hills
  • UCLA Parkside
  • UCLA Pasadena
  • UCLA Porter Ranch
  • UCLA San Luis Obispo
  • UCLA Santa Monica
  • UCLA Ventura
  • UCLA Westlake Village
  • UCLA Westwood
For Providers
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