Abstract PD7-08: Exploratory phase II trial of camrelizumab (an anti-PD-1 antibody) combined with apatinib (a VEGFR-2 inhibitor) and chemotherapy as a neoadjuvant therapy for triple-negative breast cancer (NeoPanDa03): efficacy, safety and biomarker analysis

Abstract Background: Chemotherapy serves as the primary therapeutic approach for triple-negative breast cancer (TNBC), yet its efficacy remains unsatisfactory. Methods: This study was a single-arm, open-label, single-center clinical trial (NCT05447702) involving patients with newly diagnosed stage II-III TNBC at West China Hospital. The treatment regimen consisted of camrelizumab (200 mg intravenously every 2 weeks, 12 cycles), apatinib (250 mg orally daily), and alternating chemotherapy [nab-paclitaxel (d1, 8, 15 every 4 weeks) for 4 cycles and epirubicin plus cyclophosphamide (every 2 weeks) for 4 cycles]. Results: From June 2023 to April 2024, 35 patients were enrolled, of whom 1 patient withdrew due to adverse reaction intolerance. At treatment completion, the total pathological complete response (tpCR, ypT0/is, ypN0) rate was 67.6% (23/34), and breast pCR (ypT0/is) rate was 70.6% (24/34). The overall response rate following neoadjuvant treatment reached 94.1% (32/34). Elevated levels of alanine aminotransferase (38.2%) and aspartate aminotransferase (29.4%) were the most common grade 3-4 adverse events, with no significant toxicities or treatment-related deaths reported. Genomic analysis revealed a significantly higher TP53 mutation rate in the pCR group (80% vs. 55.6%, P