| Five-year survival rate from IRIS
study of imatinib therapy for newly diagnosed patients with chronic myeloid leukemia
is 89 percent New data from the phase III IRIS study show that the five-year survival rate for patients treated with imatinib when first diagnosed with chronic myeloid leukemia is 89 percent, according to a presentation at the annual meeting of the American Society of Clinical Oncology. In addition to the data indicating patients can have a prolonged response to imatinib, the rate of disease progression in the most recent year of treatment was lower than in each of the previous years, suggesting that the longer patients are on the drug, the less likely their disease is to advance. The IRIS (for International Randomized Study of Interferon versus STI571) Trial began in mid-2000 and involved 1,106 patients at 117 centers in 16 countries. Patients enrolled in the study were in the so-called chronic phase of chronic myeloid leukemia and had received no previous chemotherapy. Half were randomized to imatinib and half to standard treatment at the time the trial started, interferon-α and cytarabine arabinoside. Patients in the interferon arm were later allowed to cross over to imatinib; only 3 percent of participants currently remain on interferon therapy. Overall survival for patients who received imatinib as initial therapy was 89 percent (95 percent if only deaths related to leukemia are considered), and 93 percent have not progressed to blast crisis. Only 5 percent of patients discontinued imatinib because of side effects; severe
side effects included skin rashes, elevated liver enzymes, and fluid retention.
More common and less severe side effects included puffiness around the eyes, mild
nausea, diarrhea, and muscle cramps. |