- Serum bilirubin levels ≤1.5 times the upper limit of the normal (ULN) range for the laboratory. Higher levels are acceptable if these can be attributed to active hemolysis or ineffective erythropoiesis. Serum AST or serum ALT levels must be ≤2.5 x ULN, or ≤5 x ULN for patients with liver involvement by lymphoma.