Contributions
Abstract: PB1823
Type: Publication Only
Background
Tyrosine kinase inhibitors (TKIs) are the golden standard in the treatment of chronic phase chronic myeloid leukemia (CP-CML) due to their high efficacy and mild toxicity profile. Because of the high price of these drugs, the use of generics is encouraged to reduce health care costs. In the literature, there is still limited data and some concerns about the effectiveness of generic imatinib (GI), although there is a growing number of countries in which it is used instead of original imatinib (OI).
Aims
The objective of this study was to evaluate efficacy and safety of GI in newly diagnosed CP-CML patients treated with frontline GI and in patients switched from OI to GI.
Methods
Cohort of 101 adult patients with CP-CML was analysed, treated with TKIs in our institution during period from August 2012 to February 2017. First group consisted of 53 patients treated with GI (Anzovip). According to European LeukemiaNet (ELN) 2013 guidelines, rate of optimum therapeutic response was analysed, as well as rate of treatment failure at 6 and 12 months. The second group consisted of 48 patients switched from OI to GI, in which the rate of achieved therapeutic response at the time of switching and the rate of maintenance of CCyR, MMR and MR4 after a minimum of 12 months under therapy with GI were both analysed. In order to investigate safety of GI, in both groups rate of hematological and non-hematological adverse effects (AEs), all grades according CTCAE criteria, were analysed.
Results
Analysis of the optimal response by ELN criteria in the group with GI showed that at 6 months 33/53 (62.3%) patients achieved CCyR, BCR-ABL<1% was in 27/52 (51.9%) patients, while 15/52 (28.8%) of patients achieved MMR. At 12 months of therapy, 35/49 (71.4%) of analysed patients achieved CCyR, and 25/49 (48.9%) achieved MMR. ELN criteria for treatment failure at 6 months fulfilled 12/53 (22.6%) patients, while at 12 months ELN criteria satisfied 13/49 (26.5%) of analysed patients. After 18 months of therapy with GI the rate of CCyR was 35/46 (76.1%) and MMR was 28/45 (62.1%) and showed trend of increase. During the median follow-up period of 23.8 months 3 patients have progressed to blast phase and total of 7 patients died. In the second group, in time of switching from OI to GI, the rates of achieved CCyR, MMR and MR4 were 82.5%, 65.8% and 49% of patients respectively. The rate of maintenance of previously achieved CCyR was 95%, of MMR 88% and of MR4 72% in the course of the median duration of GI exposure of 37.8 months. When comparing first and second group respectively, the rates of patients which have been switched to 2nd generation of TKI because of the failure or intolerance to imatinib were 27.8% vs. 24.8%, and 60.5% vs. 64.5% of them achieved secondary optimal therapeutic response (CCyR plus MMR), while 25% vs. 20% of them have been sent to BMT. Group switched from OI to GI had not significantly different non-hematological AEs of all grades compared to GI group (21.7% vs.24.2%, p=0.991). Furthermore, the rate of grade 3-4 hematological AEs were similar in both groups (13% vs 15%, p=0.952).
Conclusion
Results of this study with extended follow-up of more than four years are further evidence of that the generic imatinib is at least non-inferior to the original imatinib regarding efficacy both when used initially or as a subsequent replacement for branded imatinib.
Session topic: 8. Chronic myeloid leukemia - Clinical
Keyword(s): Therapy, imatinib, Chronic myeloid leukemia
Abstract: PB1823
Type: Publication Only
Background
Tyrosine kinase inhibitors (TKIs) are the golden standard in the treatment of chronic phase chronic myeloid leukemia (CP-CML) due to their high efficacy and mild toxicity profile. Because of the high price of these drugs, the use of generics is encouraged to reduce health care costs. In the literature, there is still limited data and some concerns about the effectiveness of generic imatinib (GI), although there is a growing number of countries in which it is used instead of original imatinib (OI).
Aims
The objective of this study was to evaluate efficacy and safety of GI in newly diagnosed CP-CML patients treated with frontline GI and in patients switched from OI to GI.
Methods
Cohort of 101 adult patients with CP-CML was analysed, treated with TKIs in our institution during period from August 2012 to February 2017. First group consisted of 53 patients treated with GI (Anzovip). According to European LeukemiaNet (ELN) 2013 guidelines, rate of optimum therapeutic response was analysed, as well as rate of treatment failure at 6 and 12 months. The second group consisted of 48 patients switched from OI to GI, in which the rate of achieved therapeutic response at the time of switching and the rate of maintenance of CCyR, MMR and MR4 after a minimum of 12 months under therapy with GI were both analysed. In order to investigate safety of GI, in both groups rate of hematological and non-hematological adverse effects (AEs), all grades according CTCAE criteria, were analysed.
Results
Analysis of the optimal response by ELN criteria in the group with GI showed that at 6 months 33/53 (62.3%) patients achieved CCyR, BCR-ABL<1% was in 27/52 (51.9%) patients, while 15/52 (28.8%) of patients achieved MMR. At 12 months of therapy, 35/49 (71.4%) of analysed patients achieved CCyR, and 25/49 (48.9%) achieved MMR. ELN criteria for treatment failure at 6 months fulfilled 12/53 (22.6%) patients, while at 12 months ELN criteria satisfied 13/49 (26.5%) of analysed patients. After 18 months of therapy with GI the rate of CCyR was 35/46 (76.1%) and MMR was 28/45 (62.1%) and showed trend of increase. During the median follow-up period of 23.8 months 3 patients have progressed to blast phase and total of 7 patients died. In the second group, in time of switching from OI to GI, the rates of achieved CCyR, MMR and MR4 were 82.5%, 65.8% and 49% of patients respectively. The rate of maintenance of previously achieved CCyR was 95%, of MMR 88% and of MR4 72% in the course of the median duration of GI exposure of 37.8 months. When comparing first and second group respectively, the rates of patients which have been switched to 2nd generation of TKI because of the failure or intolerance to imatinib were 27.8% vs. 24.8%, and 60.5% vs. 64.5% of them achieved secondary optimal therapeutic response (CCyR plus MMR), while 25% vs. 20% of them have been sent to BMT. Group switched from OI to GI had not significantly different non-hematological AEs of all grades compared to GI group (21.7% vs.24.2%, p=0.991). Furthermore, the rate of grade 3-4 hematological AEs were similar in both groups (13% vs 15%, p=0.952).
Conclusion
Results of this study with extended follow-up of more than four years are further evidence of that the generic imatinib is at least non-inferior to the original imatinib regarding efficacy both when used initially or as a subsequent replacement for branded imatinib.
Session topic: 8. Chronic myeloid leukemia - Clinical
Keyword(s): Therapy, imatinib, Chronic myeloid leukemia