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 (Astefania)

December 21, 2021
Breast Cancer
Joseph Kash, MD
Edward Cancer Center - Naperville
Edward Cancer Center - Plainfield
Nancy Knowles Cancer Center - Elmhurst

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.

Sponsor: Genentech


  • Histologically confirmed invasive breast carcinoma
  • Clinical stage: cT4/any N/M0, any cT/N2-3/M0, or cT1-3/N0-1/M0 (participants with cT1mi/T1a/T1b/N0 are not eligible)
  • No stage IV breast cancer
  • Pre-operative chemo including at least 9 weeks of taxane and 9 weeks of trastuzumab 
  • No progression since pre-op chemo
  • No prior treatment with T-DM1, or atezolizumab, or other immune checkpoint inhibitors, or with immunostimulatory or immunosuppressive agents
  • Less than 12 weeks since primary surgery
  • No history of certain malignancies within 5 years prior to screening
  • No history of idiopathic pulmonary fibrosis, organizing pneumonia, or pneumonitis
  • No active or history of active autoimmune disease or immune deficiency
  • No cardiopulmonary dysfunction or any known active liver disease
Up to 10 years
Pending IRB Approval for Recruiting
Sofia Mikac, BSN