SBRT, Chemotherapy, and AK104 Neoadjuvant Therapy for Triple-negative Breast Cancer (TNBC)

Studies have indicated that the improvement in pathological complete response (pCR) is significantly correlated with triple-negative breast cancer（TNBC）patients' overall survival (OS). Patients with TNBC have poor efficacy for neoadjuvant chemotherapy. The combination of neoadjuvant therapy with immunotherapy and chemotherapy has been demonstrated to enhance the pCR rate of TNBC patients, increasing it from 45% to approximately 60%. Therefore, how to further improve the pCR rate of TNBC breast cancer became the main objective of this study. Stereotactic radiotherapy (SBRT) not only kills tumor cells directly, but also kills the distant unirradiated tumor cells by promoting the cross-initiation of tumor-specific CD8+ T cells, a phenomenon known as the abscopal effect. Our research team has recently discovered that the triple therapy model of SBRT + anti-vascular targeting + anti-PD-1 was safe and efficacious in lung cancer patients. Cadonilimab (AK104) is an PD-1/CTLA-4 bispecific antibody. In order to improve the pCR, a single-arm, open, phase II clinical study was proposed to explore the safety and efficacy of SBRT+AK104+chemotherapy, a neoadjuvant treatment modality, in the treatment of TNBC.