Study of Pembrolizumab Treatment After CYAD-101 With FOLFOX Preconditioning in Metastatic Colorectal Cancer

This study examines whether pembrolizumab (an immunotherapy drug) given after an experimental cell therapy called CYAD-101 (with FOLFOX chemotherapy) can help patients with metastatic colorectal cancer that has not responded to earlier treatments. **You may be eligible if...** - You are 18 or older with confirmed metastatic colorectal cancer (colon or rectal) - Your cancer is not the MSI-high type (a specific genetic characteristic) - Your cancer has progressed after at least one prior treatment including FOLFOX - You have measurable disease and are in good general health (ECOG 0–1) - You have adequate organ function - You are willing to have a tumor biopsy at the start of the study **You may NOT be eligible if...** - You have had prior anti-PD-1/PD-L1 immunotherapy - You have had another investigational treatment in the last 4 weeks - You have current or prior pneumonitis requiring steroids - You have had major surgery or radiotherapy within 4 weeks - You have an uncontrolled serious illness or infection Talk to your doctor to see if this trial is right for you.