P684: A MULTICENTER RETROSPECTIVE STUDY IN CHINA: CLINICAL CHARACTERISTICS AND PROGNOSIS OF PATIENTS WITH CML-CP TREATED WITH DIFFERENT TYROSINE KINASE INHIBITORS

Background: Tyrosine kinase inhibitors are currently the first choice drugs for chronic myeloid leukemia. At present, imatinib, nilotinib, dasatinib and flumatinib are mainly used in China. Aims: We analyzed the clinical characteristics of 2545 patients with CML-CP and the curative effect after treatment with TKIs. Methods: This study retrospectively analyzed the clinical characteristics and efficacy data of 2545 CML-CP patients who received first-line and second-line treatment in 44 Chinese institutions from January 2010 to October 2022(ChiCTR2200061208). The study has been approved by the institutional ethics committee and patients provided written informed consent in accordance with the First Affiliated Hospital of Zhejiang university School of Medicine. Hematological reaction, cytogenetic reaction and molecular reaction were analyzed to evaluate the efficacy of different drugs. Statistical analyses were performed using SPSS statistics 26.0 and GraphPad Prism 9.0 software. Results: The median follow-up time of all patients in the whole cohort was 50.0 months (range 1-354 months), and the median age of 1549 males and 996 females was 48 years (range 5-92 years) (Figure A). 2545 patients were treated with drugs, as shown in the picture (Figure B).Among the first-line treatment, imatinib is the most used, the second line is dasatinib, and the third line is nilotinib(Figure C).First-line treatment includes original imatinib, generic imatinib made in Chinese, dasatinib, nilotinib, flumatinib. There was no statistical significance in achieving CHR and MR4.5 among the five groups in first-line treatment. Nilotinib is easier to achieve CCyR(P=0.006), 3-month EMR(P<0.001), 6-month ≤ 1%(P=0.001),12-month MMR(P<0.001), MR4(P<0.001) than generic imatinib. At the sametime, nilotinib is easier to achieve MR4 than original imatinib(P=0.005). Flumatinib also has the same results as niloinib, it is easier to achieve CCyR(P<0.001), 3-month EMR(P<0.001), 6-month ≤ 1%(P<0.001),12-month MMR(P<0.001), MMR(P<0.001),MR4(P<0.001) than generic imatinib. Besides, dasatinib is easier to achieve 12-month MMR than first-generation generic imatinib(P=0.003)(Figure D,E,F).Second-line TKIs include imatinib, dasatinib, nilotinib and flumatinib. There is no significant difference between different second-line TKIs in achieving CHR, CCyR, 3-month EMR, 6-month BCR-ABL ≤ 1%, 12-month MMR and MR4.5. Flumatinib is easier to achieve MMR than dasatinib(P=0.006)and nilotinib(P<0.001). And it is easier to achieve MR4 than dasatinib(P=0.002)and nilotinib(P<0.001)(Figure G,H). Summary/Conclusion: This real-world study evaluated the clinical characteristics and efficacy of different TKI drugs in the treatment of newly diagnosed CML-CP patients in China. In the first-line treatment, nilotinib is easier to achieve CCyR, 3-month EMR, 6-month ≤ 1%,12-month MMR, MR4 than generic imatinib. Nilotinib is easier to achieve MR4 than original imatinib. Flumatinib is easier to achieve CCyR,3-month EMR, 6-month ≤ 1%,12-month MMR, MMR and MR4 than generic imatinib. Dasatinib is easier to achieve 12-month MMR than first-generation generic drugs. In Second-line treatment, flumatinib is easier to achieve MMR,MR4 than dasatinib and nilotinib. This research was funded by the Key R&D Program of Zhejiang, No. 2022C03137; Public Technology Application Research Program of Zhejiang, China, No. LGF21H080003; Zhejiang Medical Association Clinical Medical Research special fund project, No. 2022ZYC-D09; the Key Project of Jinhua Science and Technology Plan, China, No. 2020-3-011.*Correspondence to: Prof Jian Huang; Prof Jie Jin.Keywords: Chronic myeloid leukemia, Treatment, Tyrosine kinase inhibitor