Neoadjuvant Checkpoint Blockade in Combination with Chemotherapy in Patients with Tripe-Negative Breast Cancer: Exploratory Analysis of Real-World, Multicenter Data

Abstract Purpose Histological subtypes of triple-negative breast cancer (TNBC) patients have an unfavorable outcome. Many randomized controlled trials have showed that neoadjuvant immunotherapy combined with chemotherapy can enhance the pathologic complete response (pCR) rate and/or long-term survival of TNBC. However, no real-world studies focusing on neoadjuvant checkpoint blockade in TNBC have been reported thus far. Methods A total of 63 early TNBC patients who were treated with pembrolizumab or camrelizumab in combination with chemotherapy between November 2019 and December 2021 at 7 institutions were included. The primary endpoint was pCR1 defined as ypT0/Tis and ypN0. Secondary endpoints included pCR2 defined as ypT0/Tis, overall response rate (ORR), disease-free survival (DFS), drug-related adverse events (AEs) and biomarkers. Results The percent of patients with pCR1 in this current study was 36.7%, and 47.6% of patients achieved a pCR2. The ORR was 82.5%. The median DFS of 33 patients with non-pCR was 20.7 months (95% CI 16.3 months-not reached). There was a significant difference in DFS between the patients who achieved a pCR and those with non-pCR tumors after neoadjuvant therapy (HR = 0.28, 95% CI 0.10–0.79; P = 0.038). The most common AEs were nausea (63.4%), fatigue (42.7%), leucopenia (30.0%) and elevated transaminase (11.7%). Conclusion Neoadjuvant checkpoint blockade in combination with chemotherapy may achieve a meaningful pCR and DFS, especially in high-risk TNBC patients. However, the pCR in this real-world research was slightly lower than those in clinical trials.