ORLANDO – Patients with newly diagnosed Philadelphia chromosome–positive chronic myeloid leukemia who took 400 mg of nilotinib twice daily had an overall survival rate of 97% after 3 years, investigators reported Dec. 6 at the annual meeting of the American Society of Hematology.
Dr. Gianantonio Rosti
Nilotinib was approved by the Food and Drug Administration in June 2010 as a first-line therapy for newly diagnosed Philadelphia chromosome–positive chronic myeloid leukemia (Ph+ CML) in chronic phase after the drug demonstrated higher and faster molecular response rates than imatinib. The current study was conducted by Dr. Gianantonio Rosti of the University of Bologna (Italy) and associates to confirm that the efficacy of nilotinib is durable over a 3-year period, the time during which most failures on imatinib occur.
The investigators enrolled 73 patients with newly diagnosed Ph+ CML in a phase II open-label, multicenter clinical trial. The patients ranged in age from 18 to 83 years, with a median age of 51 years. All patients received 400 mg of nilotinib two times per day, Dr. Rosti said at a press briefing in advance of his presentation at the meeting.
The study’s primary end point was a complete cytogenetic response rate at 12 months, meaning that no cells containing a Philadelphia chromosome were found in the patient’s bone marrow. The complete cytogenetic response rate was 78% at 3 months and 96% at 6, 12, and 18 months. Within 12 months, all patients had achieved a complete cytogenetic response at least once.
The progression-free survival and failure-free survival rates were 97% after 3 years, and the event-free survival rate was 91% after a median follow-up of 36 months.
The study is ongoing, and the current median follow-up time is longer than 3 years (30-40 months), Dr. Rosti said. Patient responses remained stable, and only one patient progressed to alternative lengthening of telomeres–-associated promyelocytic leukemia, Dr. Rosti said. A total of 97% of patients obtained a major molecular response. In addition, 70% obtained a complete molecular response, and 25% of these patients are stable, he said.
Dr. Rosti said he has received research funding from Novartis. He has also served as a consultant and on the speakers bureau and board of directors or advisory committee for the company. He has received honoraria and served on the speakers bureau for Bristol-Myers Squibb, and on the speakers bureau for Roche.