CLL with tp53 mutation

Hi everyone,

My grandpa got diagnosed with CLL and has tp53 mutation. The oncologist started him on acalabrutinib and later he will take it with venetoclax. This drug combination is part of a clinical trial and I am not too familiar with clinical trials. Does anyone have the same diagnosis and has tried this combination? How did you react to it and how effective was it? For reference he has 250k WBC count and has anemia (recently got blood transfusion to raise his hemoglobin levels).