Triplet Regimen of Metronomic Capecitabine Plus Antiangiogenic Drug and PD-1 Inhibitor as Later-Line Salvage Treatment for Patients With MSS/pMMR Metastatic Colorectal Cancer: A Retrospective Study.

Later-line treatment has demonstrated limited survival benefits in patients with metastatic colorectal cancer (mCRC). This retrospective study evaluated the efficacy and safety of a triplet regimen combining metronomic capecitabine, antiangiogenic drugs, and PD-1 inhibitors in patients with mCRC. Between January 2021 and December 2023, 21 patients with mCRC received a triplet regimen as later-line treatment. Among these, seven patients achieved objective responses, nine had stable disease, two experienced disease progression, and three showed neither complete response nor progressive disease. The objective response rate (ORR) was 33.3% (7/21), and the disease control rate (DCR) was 90.5% (19/21). The median progression-free survival (PFS) was 5.4 months (95% CI, 4.8-6.0), and the median overall survival (OS) was 10.4 months (95% CI, 6.3-14.5). A total of 17 patients experienced treatment-related adverse events, including 9 with Grade 3/4 toxicities. After 1:1 propensity score matching, 42 patients (21 receiving the triplet regimen and 21 receiving other therapies) were included. The triplet regimen was associated with significantly improved PFS (5.4 vs. 2.7 months,  = 0.01) and OS (10.4 vs. 4.7 months,  = 0.04) compared with other therapies. In conclusion, the triplet regimen demonstrated promising antitumor activity and manageable toxicity in patients with refractory mCRC.