# 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

> **NCT04873362** · PHASE3 · ACTIVE_NOT_RECRUITING · sponsor: **Hoffmann-La Roche** · enrollment: 1188 (actual)

## Conditions studied

- Breast Cancer

## Interventions

- **DRUG:** Atezolizumab
- **DRUG:** Trastuzumab Emtansine
- **DRUG:** Placebo
- **DRUG:** Trastuzumab

## Key facts

- **NCT ID:** NCT04873362
- **Lead sponsor:** Hoffmann-La Roche
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE3
- **Study type:** INTERVENTIONAL
- **Status:** ACTIVE_NOT_RECRUITING
- **Start date:** 2021-05-04
- **Primary completion:** 2028-08-31
- **Final completion:** 2034-10-02
- **Target enrollment:** 1188 (ACTUAL)
- **Last updated:** 2026-03-04


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT04873362

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT04873362, "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". Retrieved via AI Analytics 2026-06-23 from https://api.ai-analytics.org/clinical/NCT04873362. Licensed CC0.

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