1542P Updated results of a phase II clinical trial: Paclitaxel and carboplatin plus PD-1 blockades combined with anlotinib as first-line treatment for advanced oesophageal cancer

The combination of PD-1 blockades with chemotherapy is the standard first-line therapy for advanced esophageal cancer. Recent studies exhibited that anti-angiogenic drug combined with PD-1 blockades or chemotherapy demonstrated potential synergistic action and bright prospect in the combined application of anti-tumor therapy. We present updated data from the study of paclitaxel and carboplatin combined with anlotinib and PD-1 blockades in the treatment of advanced oesophageal cancer. This study was a parallel, open-label, phase Ⅱ clinical trial. A total of 90 patients (pts) with previously untreated, advanced or metastatic ESCC, with an age ranging from 18-75 years old were planned to be enrolled into three arms with an allocation ratio of 1:1:1. Arm A received TC (paclitaxel + carboplatin) + camrelizumab (200mg, q3w) + anlotinib (8mg, q3w); Arm B received TC with camrelizumab; Arm C received TC only. After 4-6 cycles of induction therapy, arm A and arm B would receive maintenance therapy until disease progression or intolerable adverse events. The primary endpoint was ORR. Secondary endpoints included PFS, OS and safety. At data cut-off date (Apr. 30, 2023), a total of 90 pts was enrolled. 25 of 30 pts achieved partial response (PR) and 2 pts achieved complete response in arm A, 13 of 30 pts achieved PR in arm B, and 7 of 30 pts achieved PR in arm C. The ORR were 90.0% in arm A, 43.3% in arm B, and 26.7% in arm C. The median PFS (95% CI) were 13.4 months (10.1-16.8) in arm A, 7.2 months (3.6-10.9) in arm B, and 4.8 months (4.0-5.6) in arm C. The median OS was not reached. The rate of treatment related adverse events (TRAEs) of any grade was 100% in all three groups, and grade 3 TRAEs were 30.0%, 23.3% and 13.3%, respectively. The most common grade 3 TRAEs were thrombocytopenia (8.9%), decreased white blood cell count (6.7%), neutropenia (5.6%). No grade 4 or 5 TRAEs were observed. Addition of anlotinib to immunotherapy plus chemotherapy as first-line therapy showed amazing clinical outcomes in ESCC pts with a manageable safety profile. The study was still ongoing, and the data would be updated to confirm this conclusion subsequently.