TKI Duration and Molecular Response Pivotal for Survival With Chronic Myeloid Leukemia

For patients with chronic myeloid leukemia (CML), relapse-free remission with deep molecular response is possible, though the duration of tyrosine kinase inhibitor (TKI) treatment is important, according to a study presented at the European Hematology Association’s 21^st congress.¹

Researchers enrolled 868 patients in the chronic phase of CML to determine the optimal time for discontinuing TKI treatment. Of the enrolled patients, data from 772 were evaluated; time from diagnosis to TKI discontinuation varied from 36.7 months to 270.7 months, with a median of 92.7 months.

Molecular relapse-free survival was 62% at 6 months, 56% at 12 months, and 51% at 24 months. Duration of TKI treatment was positively correlated with the duration of a deep molecular response, defined as bcr-abl levels in blood samples being 4 logs lower than before treatment (MR4).

Researchers involved in this EURO-SKI study plan a 3 year follow-up; the authors concluded that duration of TKI treatment and MR4 prior to discontinuation are pivotal for relapse-free survival. Imatinib made up 94% of first-line TKIs for patients enrolled in this study; dasatinib and nilotinib made up 2% and 4%, respectively.

Reference

1. Richter J, Mahon F, Guilhot J, et al. Stopping tyrosine kinase inhibitors in a very large cohort of chronic myeloid leukemia patients: results of the EURO-SKI trial. Paper presented at: 21^st Congress of the European Hematology Association; June 2016; Copenhagen, Denmark.