Molecular Pathology Laboratory Network

A multi-center study showed the development of chronic myeloid leukemia (CML) slowed down with Imatinib (Gleevec) treatment; and patients with CML who respond to initial treatment have a normal life expectancy.

In a study of the long-term effects of the drug, survival of patients with a complete cytogenetic remission was not significantly different from the general population, according to Carlo Gambacorti-Passerini, MD, of the University of Milano Bicocca in Monza, Italy, and colleagues.

Imatinib, a tyrosine kinase inhibitor that targets the Philadelphia chromosome characteristic of CML, was the first to yield complete and lasting responses and is now widely used as first-line treatment. However, most information on the long-term effects of the drug has come from industry-sponsored trials at selected centers, according to the researchers.

To fill the gap, the independent Imatinib Long-Term (Side) Effects study - conducted in 27 centers on five continents - enrolled 832 patients who started the drug treatment before 2005 and were in complete cytogenetic remission after two years of therapy. Incidence of the first serious and nonserious adverse events and loss of complete cytogenetic remission were estimated according to the Kaplan-Meier method and compared with the standard log-rank test. Attainment of negative Philadelphia chromosome hematopoiesis was assessed with cytogenetics and quantitative polymerase chain reaction.