Imatinib Safe and Effective on Long-Term Use in CML

The selective BCR-ABL1 kinase inhibitor imatinib mesylate (Gleevec) has been found to be safe and effective following almost 11 years of follow-up in patients with chronic myeloid leukemia (CML). The results of this long-term study have been published in the New England Journal of Medicine.

Driven by a basic research finding that the BCR-ABL1 kinase drives disease progression in CML, imatinib was developed as an inhibitor of this kinase and received FDA approval in 2001. The current study was a multicenter, randomized crossover trial that assigned 1106 patients to either the imatinib arm or interferon alfa plus cytarabine arm. The study was conducted at 177 cancer centers across 16 countries. Primary trial outcomes were overall survival (OS), response to treatment, and serious adverse events (SAEs).

“The long-term success of this treatment confirms the remarkable success we’ve seen since the very first Gleevec trials," Brian Druker, MD, director of the Oregon Health & Science University Knight Cancer Institute, who led the original trial for imatinib and co-authored the current paper said in a statement. "This study reinforces the notion that we can create effective and non-toxic therapies.”

At a median follow-up of 10.9 years, OS was 83.3%. Nearly 50% of patients completed the assigned treatment with imatinib and 82.8% had a complete cytogenetic response. SAEs were more common in only the first year of treatment.

“Our results demonstrating Gleevec’s high efficacy in CML tell us to realize the full promise of precision cancer medicine, we need to diagnose and treat patients earlier in the disease course,” Druker said.

In addition to CML, the drug has been found to be effective against pediatric CML and gastrointestinal stromal tumors (GIST). Patients with GIST treated with imatinib have seen their life expectancy increase from 18 months to over a decade.

Imatinib mesylate is also indicated for acute lymphoblastic leukemia and myelodysplastic syndrome.

Reference

Hochhaus A, Larson RA, Guilhot F, et al. Long-Term outcomes of imatinib treatment for chronic myeloid leukemia. N Engl J Med. 2017;376(10):917-927. doi: 10.1056/NEJMoa1609324.