Generic Imatinib in a Patients with Chronic Myeloid Leukemia in Chronic Phase- a Single Centre Experience

Imatinib (Gleevec) has shown long-term efficancy and safety in published randomized clinical trials. Anzovip (Imatinib) is a new generic drug produced by Zdravlje Actavis,which was approved by the Medicines and Medical Devices Agency of Serbia in January 2012. In July 2012, National Health Insurance Fund of Serbia introduced this drug in the positive list. All the patients using Glivec were switched to Anzovip and all newly diagnosed patients started with Anzovip therapy. In this study, hematologic and cytogenetic responses were evaluated in CML patients who received generic Imatinib as the first line therapy and in patients who switched from branded Imatinib to an Imatinib copy drug.

Materials and methods. During August and September 2012, all the patients were switched from Glivec to Anzovip and all new CML patients were treated with Imatinib copy. 55 patients treated with branded Imatinib were switched to generic Imatinib. Out of 17 newly diagnosed patients with CML-CP, who started with generic Imatinib, 7 patients could be followed up for 18 months. All patients underwent hematologic, cytogenetic monitoring based of the recommendations of the ELN.

Results. These are the results of using Anzovip after 18 months. Of the 55 patients who were switched from branded Imatinib to Imatinib copy, 11 patients (20 %) have lost complete cytogenetic response they already had, but without signs of biological illness transformation. They were switched to 2^nd line therapy nilotinib.Of the 7 newly diagnosed patients who started with genereic Imatinib, all 7 patients (100%) have achieved complete hematologic response (CHR) in the period of 6 months. 3 (42,8%) patients have achieved CCgR and 2 patients (28,6%) have achieved MMR in the period of 12 months. 57% of patients have switched to second generation of TKI because of failure or intolerance according to ELN and national recommendation. The drug has been well tolerated, wild mild adverse event, more frequently, fluid retention and gastrointestinal symptoms. Only one patient have had skin changes grade ¾ and he has been switched to second generation of TKI.

Conclusions. It is unknown whether patients, who responded to branded Imatinib and than switched to its copy versions, will tolerate the copy drug and maintain the previous response. Because of that, it is important to careful follow up of a selected patients several months after the switch to generic imatinib. Despite of the small number of patients who started with Imatinib copy, our results in term of hematologic and cytogenetic response were close to the international series.