SBRT, Chemotherapy, and AK112 Neoadjuvant Therapy for Luminal-type Breast Cancer

Studies have indicated that the improvement in pathological complete response (pCR) is significantly correlated with luminal breast cancer patients' overall survival (OS). Patients with luminal breast cancer have poor efficacy for neoadjuvant chemotherapy. The combination of neoadjuvant therapy with immunotherapy and chemotherapy has been demonstrated to enhance the pCR rate of luminal-type breast cancer patients, increasing it from 13-15% to approximately 24%. Therefore, how to further improve the pCR rate of luminal-type 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. Ivonescimab (AK112) is an anti-PD-1/VEGF-A 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+AK112+chemotherapy, a neoadjuvant treatment modality, in the treatment of luminal breast cancer.