ACALABRUTINIB (a KAL a BROO ti nib) treats leukemia and lymphoma. It works by blocking a protein that causes cancer cells to grow and multiply. This helps to slow or stop the spread of cancer cells. This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.These results mean that acalabrutinib is a useful chemotherapy-free option and gave better results than chemoimmunotherapy with low side effects for patients with CLL/SLL who are starting their treatment for leukemia.