The drug rituximab prolonged the lives of some people with chronic lymphocytic leukemia (CLL), according to the findings of two clinical trials.The trials compared the effectiveness of a combination of rituximab and the chemotherapy drug fludarabine to the effectiveness of fludarabine alone.The studies found that, after an average of 43 months, the combination therapy increased progression-free survival by 22 percent and overall survival by 12 percent compared to fludarabine alone.The results were presented Dec, 8 at the American Society of Hematology’s annual meeting in San Diego.