Background: Imatinib is the first TKI that was officially approved by the Food and Drug Administration (FDA) for the treatment of patients (pts) with CP-CML and it is the most commonly used treatment in CML pts on the international scene. Generic imatinib was offered and accessible as frontline treatment of CML in china in June 2013, which predictably lowered the cost of CML therapy. However the statistics regarding their effectiveness and tolerability in greater proportion of the population of CML pts are not available. (ClinicalTrials. gov number, NCT02317159.)
Aim: To evaluate the efficacy and safety of generic imatinib in the treatment of pts that were newly diagnosed with CP-CML.
Methods: In this multi-center, prospective open-label study, 75 pts with CP-CML were enrolled to receive generic imatinib mesylate capsules at a dose of 400 mg once daily. The primary end point was major molecular response (MMR) by 12 months. Imatinib plasma level and adverse events (AEs) were assessed.
Results: The Median age at diagnosis was 46 years (range 19-75 years), and 50 pts (66.7%) were male. The median follow-up was 22.1 (range0.5-24) months. 35 pts (44%), 26 pts (34.7%) and 12 pts (16%) were in low, intermediate and high risk group, respectively, according to Sokal prognostic score (Not available in 2 pts). By 12 months, the cumulative rate of MMR (BCR-ABL1IS ≤0.1%) was 42.7% (32/75), and the cumulative rate of complete cytogenic response (CCyR) was74.7% (56/75). Complete hematologic response (CHR), CCyR, MMR rate at 3 months,6 months and 12 months were shown in Table 1. For pts who presented with BCR-ABL1 IS≤ 10% at 3 months, had better response as compared with those with BCR/ABL1IS> 10% (Table 2). The estimated progression-free survival at 12 months was 94.7%. Imatinib plasma levels at 29 days on imatinib were variable in individual, with 1522.9±775.3 ng/mL for median level (rang 394.4 to3891 ng/mL). Although those numerical values showed difference, no statistically significant correlations were found between imatinib plasma level and CCyR or MMR(P=0.902;P=0.349). The incidents and profile of AEs were similar to those reported previously.
Conclusion: This study confirmed that generic imatinib produced in China is effective and well-tolerated in Chinese CP-CML pts. The outcome of generic imatinib in the treatment of CP-CML is similar to brand imatinib reported in the literatures. The introduction of generic imatinib at a reduced and affordable cost may strikingly impact the cost of care for CML and improve the clinical outcomes of CML in China.
No relevant conflicts of interest to declare.
