SABCS 2023: Neoadjuvant Chemotherapy Plus Lead-In vs Concurrent Nivolumab in Triple-Negative Breast Cancer

By: Julia Fiederlein Cipriano, MS
Posted: Tuesday, December 19, 2023

According to Sherene Loi, MD, PhD, of Peter MacCallum Cancer Centre, Melbourne, Australia, and colleagues, in patients with stage I or II triple-negative breast cancer, neoadjuvant nivolumab plus nonanthracycline chemotherapy was efficacious regardless of whether the PD-1 inhibitor was administered before or during the 12-week treatment period. The results of the multicenter phase II BCT1902/IBCSG 61-20 Neo-N trial, which were presented during the 2023 San Antonio Breast Cancer Symposium (SABCS; Abstract LBO1-03), suggested the regimen was also well tolerated.

“Patients with immune-enriched tumors…had very high pathologic complete response rates, identifying a subpopulation for whom a 12-week anthracycline-free chemotherapy regimen with nivolumab may be appropriate,” the investigators added.

Prior to undergoing surgery, 108 evaluable patients were randomly assigned to receive either a 2-week lead-in of nivolumab monotherapy followed by nivolumab plus carboplatin and paclitaxel for 12 weeks (arm A) or nivolumab plus carboplatin and paclitaxel for 12 weeks followed 2 weeks later by nivolumab monotherapy (arm B).

The pathologic complete response rates were 50.9% and 54.5% in arms A and B, respectively; the overall rate was 52.8%. The overall rate of residual cancer burden (RCB)-0 and RCB-I was 68.5%; the rates in arm A vs B were 64.2% and 72.7%, respectively. The overall pathologic complete response rates were 66.7% and 45.7% in patients with high and low baseline levels of stromal tumor–infiltrating lymphocytes and 70.6% and 33.3% in those with PD-L1–positive and –negative tumors, respectively. The pathologic complete response rate was 48.6% in patients with stage I breast cancer and 54.9% in those with stage II disease.

According to the investigators, treatment-related adverse events were comparable between the arms; they reported toxicities of grades 3 and 4 in 64.8% of patients. Early discontinuation of treatment with nivolumab was documented in 15.7% of the population. A total of 20.4% of patients experienced any-grade immune-related endocrine dysfunction.

Disclosure: For full disclosures of the study authors, visit sabcs.org.

2023 San Antonio Breast Cancer Symposium

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