Venetoclax Resistance Landscape in Chronic Lymphocytic Leukemia

This study is investigating why some patients with chronic lymphocytic leukemia (CLL) — a slow-growing blood cancer — stop responding to a drug called venetoclax. Researchers will analyze tumor samples from patients whose disease has progressed or transformed while on venetoclax to understand the biological reasons for resistance. **You may be eligible if...** - You are 18 or older - You have been diagnosed with CLL (chronic lymphocytic leukemia) - Your disease has relapsed or stopped responding to venetoclax treatment - You have tumor samples available for analysis - You are covered by the French Social Security system **You may NOT be eligible if...** - You or your legal guardian refuses to participate Talk to your doctor to see if this trial is right for you.