Comparing branded and generic imatinib treatment in patients with chronic myeloid leukemia

This study aimed to compare the effectiveness and safety of generic and branded imatinib in patients with newly diagnosed chronic-phase chronic myeloid leukemia.  

This study concluded that generic and branded imatinib had similar effectiveness and safety in these patients.  

Imatinib is a targeted therapy used for the treatment of chronic myeloid leukemia (CML) including chronic phase CML (CP-CML). Glivec is the branded version of imatinib. A generic version is also available. A generic drug is a medication created to be the same as an already approved brand-name drug in dose, safety, quality. However, generic medications may come at a lower cost. 

It was unknown how the effectiveness and safety of branded and generic imatinib treatment compared in patients with CP-CML. 

This study involved 442 adult patients with CP-CML. 236 patients received generic imatinib and 206 received branded imatinib (Glivec). In the generic group, there were more patients with rural household registration, lower education level, and divorced or widow status when compared to the branded group. In the generic group, there were also more patients with higher white blood cell counts, enlarged spleen, and longer intervals from diagnosis to starting imatinib when compared to the branded group.  

The 4-year probability of achieving a complete cytogenetic response (CCR – no cells contain Philadelphia chromosome) was 97% for the generic group compared to 97.3% for the branded group. The 4-year probability of achieving a major molecular response (MMR – low level of BCR-ABL gene in the blood) was 87.8% for the generic group compared to 90.1% for the branded group. The 4-year probability of achieving deep molecular response (DMR – a sign of disease remission) was 32.5% for the generic group compared to 38.8% for the branded group.  

Failure-free survival at 4 years was 77.3% for the generic group compared to 81.4% for the branded group. Survival without cancer worsening after 4 years was 94.4% for the generic group compared to 95.8% for the branded group. The overall survival (OS) rate at 4 years was 96.8% for the generic group compared to 98.3% for the branded group. 

7.7% of the generic group and 8.3% in the branded group developed serious blood-related side effects. There was also no difference between groups in terms of other side effects such as swelling in the feet, tiredness, and muscle aches.

This study concluded that generic and branded imatinib had similar effectiveness and safety in CP-CML patients. 

This study was based on medical records. Patients were not randomly assigned to receive the drug. Also, patients' characteristics were different at the beginning of the study. This may affect the results. Further controlled studies are needed.