Safety and efficacy of irinotecan, oxaliplatin, and capecitabine (XELOXIRI) regimen with or without targeted drugs in patients with metastatic colorectal cancer: a retrospective cohort study

Background Five-fluorouracil, folinic acid, oxaliplatin and irinotecan (FOLFOXIRI) regimen is used as the first-line treatment for metastatic colorectal cancer (mCRC). The use of capecitabine, an oral fluoropyrimidine pro-drug, is feasible and safe; hence, it provides an interesting alternative to 5-fluorouracil in the abovementioned regimen. This study aimed to evaluate the efficacy and safety of capecitabine, oxaliplatin, and irinotecan (XELOXIRI) regimen use with or without targeted drugs in Chinese patients with mCRC. Methods We conducted a retrospective, longitudinal cohort study of patients with mCRC who received XELOXIRI regimen with or without targeted drugs (bevacizumab or cetuximab) every 2 weeks between January 2017 and November 2019 at the National Cancer Center/Cancer Hospital, the Chinese Academy of Medical Sciences, and Peking Union Medical College. Treatment efficacy was assessed by investigators by evaluating the objective response rate (ORR) and disease control rate (DCR). Overall survival (OS) was assessed using Cox proportional hazards models. The adverse events were also analyzed. Results Sixty-one consecutive patients were examined and followed up for survival. As of November 8, 2021, the median follow-up time was 35.4 months. Disease progression and death occurred in 50 (82%) and 38 (62%) patients, respectively. The median treatment duration of XELOXIRI with or without bevacizumab or cetuximab was 10 cycles (range, 1–12 cycles). The median OS and PFS were 32.2 months (95%CI [24.8–39.6]) and 9.3 months (95% CI [8.1–10.5]), respectively. The ORR of 48 patients with measurable lesions was 70.8%, and the DCR was 89.6%. RAS / BRAF wild-type (HR 0.39; 95% CI [0.16–0.96], p = 0.04) and metastatic organs > 2 (HR 3.25; 95% CI [1.34–7.87], p = 0.009) were independent prognostic factors for OS. The incidence of any grade of adverse events (AEs) was 96.7% (59/61). Grade ≥ 3 AEs included neutropenia (19.7%), leukopenia (9.8%), diarrhea (3.3%), vomiting (3.3%), febrile neutropenia (1.6%), and thrombocytopenia (1.6%). No treatment-related death occurred. Conclusion The use of the XELOXIRI regimen with or without a targeted drug was effective, with a manageable toxicity profile in Chinese patients with mCRC.