Neoadjuvant Treatment of Fulzerasib Plus Cetuximab N01 in KRAS G12C Mutated Locally Advanced Colorectal Cancer With or Without Resectable Metastases
Eligibility: age 18-80 years, ECOG 0-1, histologically confirmed colorectal adenocarcinoma (stages T4N0-2M0, T3N2M0, T0-4N0-2M1a \[resectable metastases confirmed by multidisciplinary discussion\]), KRAS G12C mutation, NRAS/BRAF wild-type, pMMR/MSS. Neoadjuvant therapy: fulzerasib (qd, po, d1-28) plus cetuximab N01 (500 mg/m², IV, q2w) for 2 months. Safety assessments (CBC, liver/renal function, QoL) every 2 weeks; CEA monthly. Tumor response assessed by CT chest/abdomen and rectal MRI at 2 months. Radical surgery for responders (cCR patients may choose watchful waiting). Adjuvant therapy per pathological response. Follow-up: CEA every 3 months, CT every 6 months. Primary endpoint: overall response rate (pCR or cCR). Secondary endpoints: ORR, 1-year DFS, 3-year DFS, QoL. RECIST v1.1 for disease assessment; NCI-CTCAE v5.0 for adverse events. Hypothesis：This chemotherapy-free neoadjuvant regimen combining a KRAS G12C inhibitor with cetuximab N01 may enhance perioperative safety and improve prognosis and quality of life in patients with KRAS G12C-mutated CRC.
• The subjects voluntarily joined this study, signed an informed consent form, and showed good compliance;
• Age: 18-80 years old, PS score 0-1;
• Colorectal adenocarcinoma diagnosed by histopathology, preoperative staging: T4N0-2M0, T3N2M0, T0-4N0-2M1a (with metastatic lesions present, requiring MDT evaluation as resectable); PMMR/MSS, KRAS G12C mutation, and both NRAS and BRAF wild-type
• Locally advanced colorectal cancer requires initial diagnosis of patients who have not received systematic treatment in the past. Patients with resectable metastatic lesions are required to have not received targeted therapy in the past, and new metastases after adjuvant therapy can be included in this study.
• The main organ functions well and meets the following criteria:
‣ Blood routine examination criteria (corrected for no blood transfusion or use of hematopoietic stimulating factor drugs within 7 days before screening): hemoglobin (HGB) ≥ 90g/L (if chronic anemia is caused by chronic blood loss from the tumor and the researcher evaluates the stability of vital signs, it can be included in the group); absolute neutrophil count (NEUT) ≥ 1.5 × 109/L; platelet count (PLT) ≥ 75 × 109/L;
⁃ Biochemical tests must meet the following standards: total bilirubin (TBIL) ≤ 1.5 times the upper limit of normal (ULN) (Gilbert syndrome subjects, ≤ 3 × ULN); alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 2.5 ULN; serum creatinine (CR) ≤ 1.5ULN or creatinine clearance rate (CCR) ≥ 50ml/min.
⁃ Coagulation or thyroid function tests must meet the following criteria: prothrombin time (PT), activated partial thromboplastin time (APTT), international normalized ratio (INR) ≤ 1.5 × ULN (without anticoagulant therapy); thyroid stimulating hormone (TSH) ≤ ULN; If there are abnormalities, T3 and T4 levels should be examined (if there is no T3 in the center, T4 can be replaced by FT3 and FT4), and if the level is normal, it can be selected.
• Cardiac ultrasound evaluation: Left ventricular ejection fraction (LVEF) ≥ 50%.