Impact of Neoadjuvant Immunotherapy in Early Stage Breast Cancer Before Standard Therapy

The aim of this study is to determine, using immunohistochemistry (IHC) on biopsies and surgically removed tumor if short-treatment immunotherapy with atezolizumab monotherapy or in combination with other biologic agents (ipatasertib / Bevacizumab / Trastuzumab / Pertuzumab) is associated with increased levels of activated GzmB+ CD8+ T cells from baseline to post treatment sample. Moreover, from baseline to post treatment sample, evolution of others biomarkers will be studied : GzmB/CD8, CD8/FoxP3, CD8/CD68 in IHC, cell proliferation, PD-L1, MHC-I, change in gene expression (RNA-Seq). Tjis study aim also to assess the safety and tolerability of study treatments in this population and to determine the effect of short-term immunotherapy treatment in pCR at surgery. Patients will undergo tumor biopsies at screening and 15 days after the beginning of treatment (if they start neoadjuvant chemotherapy) / at surgery, in order to evaluate in IHC evolution of activated GzmB+ CD8+ T cells and evaluate other markers It targets 2 different cohorts: newly diagnosed, non-metastatic early-stage triple-negative (TNBC) or HER2+ breast cancer. TNBC cohort is composed of 2 open-label, randomized arms, HER2+ of 2 arms. A maximum of 185 patients will be included in the trial Tumor evaluation will be performed by clinical examination and Breast echography at baseline and end of treatment visit. The safety of the product will be assessed at each cycle, through complete clinical exams, biological tests and through the collection of ongoing toxicities or adverse events.