Generic Imatinib in Chronic Myeloid Leukemia: Survival of the Cheapest.

Abstract

The patent expiration of imatinib mesylate (Gleevec; Novartis) on February 1, 2016, has brought the focus back on generic versions of the drug, and an opportunity to provide a safe and cost-effective alternative. The objective of our study was to determine the molecular and cytogenetic responses, survival endpoints (event-free survival, failure-free survival, transformation-free survival, overall survival), and safety of innovator and generic brands of imatinib. In this retrospective analysis, data from 1812 patients with chronic myeloid leukemia treated with frontline imatinib mesylate (innovator/generic) at a single institution between 2008 and 2014 is included. Of these, 445 were excluded owing to inadequate data and follow-up, and a further 156 were excluded as they were in either the accelerated phase or blast crisis at diagnosis. Thus, data from 1067 patients who were treated with Gleevec (Novartis), and 144 patients with Veenat (NATCO) were available for analysis, and included in the study. There was no significant difference in event-free survival (P= .05), failure-free survival (P= .07), transformation-free survival (P= .12), or overall survival (P= .24) between the 2 groups. The frequency of reported nonhematologic adverse events and hematologic adverse events was comparable between the study groups. The findings of the present study showed comparable efficacy and safety of the generic and innovator versions of imatinib in the treatment of patients with chronic myeloid leukemia.