The FDA has granted accelerated approval of Bristol-Myers Squibb's cancer drug Sprycel for the treatment of a rare type of leukemia, the agency has announced.

Sprycel (dasatinib) is an oral treatment for adult patients with chronic myeloid leukemia (CML), a rare cancer characterized by the uncontrolled growth of white blood cells. The FDA granted regular approval for Sprycel as a treatment for adults who have Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL), a more serious form of leukemia. Bristol-Myers Squibb said it anticipates that the drug will be available nationwide within days.

Both approvals are for patients who have experienced resistance or intolerance to prior therapy. For many patients with CML the risk of developing resistance to treatment increases with the number of years of prior treatment and the severity of the disease, and patients with Ph+ALL generally develop resistance more quickly than CML patients, the FDA said.

Sprycel works by reducing the activity of one or more proteins responsible for the overproduction of leukemia cells in the bone marrow of patients with these two diseases, allowing normal red cell, white cell and blood platelet production to resume.