Phase II Study of Irinotecan, Trifluridine/tipiracil (TAS-102) plus Bevacizumab as a Later-line Therapy for Patients with Metastatic Colorectal Cancer (mCRC): a prospective single-center explorative study

To explore the efficacy and safety of the combination of irinotecan, trifluridine/tipiracil (TAS-102), and bevacizumab in a later‐line setting for metastatic colorectal cancer (mCRC) patients. This was a single-center, phase II trial. The mCRC patients who are refractory to standard first-line and second-line treatment are eligible. Patients who previously received irinotecan while progressing during maintenance therapy are also eligible. The primary endpoint was the objective response rate (ORR). Between August 1, 2022, and September 30, 2023, 35 patients were enrolled, and 31 of them were evaluable for efficacy. The ORR was 25.8% (8/31), and the disease control rate (DCR) was 93.5% (29/31). As of April 30, 2024, the median progression-free survival (PFS) was 9.2 months (95% CI 6.285-12.115), whereas the median overall survival (OS) was not reached with the 1-year OS rate of 73.5%. The most common grade 3/4 treatment-related adverse events were neutropenia (34.3%), anemia (17.1%), and thrombocytopenia (8.6%). Irinotecan, TAS-102 plus bevacizumab regimen preliminarily demonstrated promising efficacy with tolerable toxicity for mCRC patients as later‐line treatment. This regimen warrants further exploration in refractory mCRC patients.