Studies have shown that some patients with chronic myelogenous leukemia (CML) who have responded well to the drug imatinib can stop taking the drug after they achieve a very low level of CML cells, and that nearly half of them do not experience a recurrence of their cancer even after being off imatinib for about three years. Among those who do have a recurrence, almost all who begin taking imatinib again respond to treatment.
The purpose of this study is to see if some patients who respond well to a similar CML drug, called nilotinib, can safely stop taking this drug. Patients coming into the study must have a very low level of CML cells in their blood, and switch from imatinib to nilotinib. Those whose CML levels fall to undetectable levels (using molecular tests, a status called “complete molecular response”) will then stop taking nilotinib. These patients will be randomly assigned to stop nilotinib therapy after one year (half of the patients) or two years (the other half of the patients).
Researchers will see how long patients can maintain a complete molecular response, and also see if those whose CML returns can achieve a molecular response again after resuming nilotinib. Nilotinib is a capsule that is taken orally (by mouth).