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

ID#: NCT04873362

Age: 18 years - 66+

Gender: All

Healthy Subjects: No

Study Phase: Phase 3

Recruitment Status: Recruiting

Start Date: May 04, 2021

End Date: October 26, 2034

Contact Information:
Reference Study ID Number
888-662-6728 (U.S. and Canada)
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.

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: 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