Clinical Study on the First-line Treatment of Advanced Colorectal Cancer With Simultaneous Infusion of Levozolinate for Injection and 5-FU

Inclusion Criteria: 1. The subjects voluntarily joined this study and signed the informed consent form. 2. Age: 18 to 75 years old, gender not limited; 3. ECOG PS score: 0-2 points 4. Patients with unresectable or metastatic colorectal cancer confirmed by histology or cytology, where the primary tumor location and the status of RAS and BRAF are known; 5. No previous treatment for unresectable or metastatic lesions has been received; 6. There is at least one measurable lesion in accordance with the RECIST 1.1 standard; 7. In the pre-treatment examination indicators, there was no serious hematopoietic function abnormality, and the functions of the heart, lungs, liver and kidneys were basically normal. 1. Hemoglobin (Hb) ≥70 g/L; 2. White blood cell count (WBC) ≥3.0×109/L; Neutrophil count (NEUT) ≥1.5×109/L; 3. Platelet count (PLT) ≥100×109/L; 4. Liver function (aspartate aminotransferase AST or alanine aminotransferase ALT) level ≤2.5 times the upper limit of normal value (ULN); Renal function (serum creatinine sCr) level ≤1.5 times the upper limit of the normal value (ULN). Total bilirubin (TBIL) ≤1.5 times the upper limit of the normal value (ULN). 8. The expected survival period is more than three months. Exclusion Criteria: 1. Those who have been confirmed to be allergic to the test drug and/or its excipients; 2. Those with contraindications to chemotherapy; 3. Colorectal cancer patients with MSI-H or dMMR; 4. Pregnant or lactating women; 5. There is a history of other malignant tumors in the past; 6. Those with systemic internal diseases and mental disorders who are not suitable for chemotherapy; 7. Patients who were determined by the researchers to be unsuitable for inclusion in this study.