Clofarabine improves cytarabine response in AML
Last Updated: 2012-06-12 17:35:10 -0400 (Reuters Health)
NEW YORK (Reuters Health) - Although overall survival is not increased, adding clofarabine to cytarabine therapy significantly improves event-free survival in older patients with refractory or relapsed acute myelogenous leukemia (AML), researchers report.
By improving the overall response rate and event-free survival, the combination "allowed more patients to proceed to transplant in remission," the research team wrote in a May 14 online paper in the Journal of Clinical Oncology.
Dr. Stefan Faderl of the University of Texas MD Anderson Cancer Center, Houston, and colleagues note that while five-year survival in younger AML patients went from 11.9% in 1975 to 52.1% in 2002, the increase in age-50-and-older patients was only from 4.4% to 11.2%.
The median age of the 320 patients in the new study was 67. They were randomized to receive either clofarabine plus cytarabine or a placebo plus cytarabine for five consecutive days.
There was no difference in the primary end point of overall survival with the combination (6.6 vs 6.3 months). However, the overall response rate was significantly better (46.9% vs 22.9%), as were four-month event-free survival (37.7% vs 16.6%) and event-free survival overall (hazard ratio, 0.63).
The 30-day induction mortality rate was greater, however: 16% vs 5% (p<0.01), and serious adverse events were more common in the combination group (60% vs 49%). Serious infections were also more common (38% vs 22%) as were deaths because of treatment-related adverse events (6.2% vs 1.9%).
The researchers note that "hematopoietic stem-cell transplantation (HSCT) after remission induction in this setting may lead to long-term remissions or cure." Among transplant patients, 16% of the combination patients versus 9% of the other patients were in remission after study treatments at the time of HSCT.
"Study follow-up continues," they conclude, "and the role of clofarabine in the treatment of adult patients with AML is being investigated in other randomized trials."
Dr. Faderl did not respond to requests for comments.
J Clin Oncol 2012.