Credit: CDC
NEW ORLEANS—New data indicate a trend for longer overall survival and event-free survival in newly diagnosed chronic myeloid leukemia (CML) patients on nilotinib versus imatinib.
Five-year data from the phase 3 ENESTnd study demonstrate higher rates of early and deeper molecular response in newly diagnosed CML patients taking nilotinib, as well as a reduced risk of progression compared to imatinib.
These results were presented at the 2013 ASH Annual Meeting as abstract 92.
“These new, updated data reaffirm the superiority of nilotinib over imatinib at achieving deeper molecular responses and provide even more evidence supporting nilotinib as an appropriate treatment of choice in newly diagnosed patients,” said Giuseppe Saglio, MD, of the University of Turin in Italy.
“Now, we are looking at how deeper molecular responses may help guide our approach towards how we treat CML in the future.”
The 5-year ENESTnd data showed that nilotinib can produce superior responses across various Philadelphia chromosome-positive CML patient populations, including newly diagnosed patients. Results showed higher rates of early and deeper sustained molecular response, known as MR4.5.
The difference in the rates of MR4.5 continued to be higher when nilotinib was given at 300 mg or 400 mg twice daily, when compared to imatinib (MR4.5: 6%-10% difference by 1 year, 21%-23% difference by 5 years).
“The most important endpoint is cumulative incidence of MR4.5,” Dr Saglio said. “At 5 years, this is achieved by 54% of those in nilotinib-300-mg group, 52% in the nilotinib-400-mg group, and 31% in the imatinib group. And the curves are still diverging.”
The data also indicate a trend for higher overall survival and event-free survival rates in patients treated with nilotinib.
Fifteen patients treated with imatinib had CML-related deaths, compared to 6 patients in the arm receiving nilotinib at 300 mg twice daily and 4 patients in the arm receiving nilotinib at 400 mg twice daily.
Few new adverse events and laboratory abnormalities were observed between year 4 and year 5. Rates of patients with adverse events leading to discontinuation were 11.1% in the 300-mg nilotinib group, 17.7% in the 400-mg nilotinib group, and 13.2% in the imatinib group.
Dr Saglio noted that select cardiac and vascular events are slightly more frequent on nilotinib versus imatinib. But there has been no increase in the annual incidence of these events over time.
Therefore, Dr Saglio concluded, “Nilotinib, a standard-of-care frontline therapy option for newly diagnosed, chronic-phase CML patients, affords superior efficacy compared with imatinib, including higher rates of early molecular response (which is associated with improved long-term outcomes), higher rates of deep molecular response, and a lower risk of disease progression. Nilotinib continues to show good tolerability with long-term follow-up.”
