Influence of pharmacokinetics-related polymorphisms on asciminib exposure in patients with Japanese chronic myeloid leukemia.

[PURPOSE] The effects of polymorphisms in CYP3A4, UGT2B7, ABCB1, ABCG2, ABCC2, NR1I2, and AHR genes on asciminib exposure were evaluated in Japanese patients with chronic myeloid leukemia.

[METHODS] Plasma concentrations of asciminib (40 mg twice daily [BID] or 80 mg once daily [QD]) were measured by high-performance liquid chromatography. Statistical analysis was performed using SPSS (P < 0.05).

[RESULTS] For both regimens, the median asciminib area under the concentration-time curve (AUC) was significantly higher in female than in male patients (P = 0.009 and 0.004, respectively). Significant correlations were observed between the asciminib AUC of 40 mg BID or 80 mg QD and body weight (P = 0.042 and < 0.001, respectively). The asciminib AUC of 40 mg BID in patients with the -25385 T allele of the NR1I2 -25385C > T polymorphism was significantly lower than that in patients with the -25385C/C genotype (5363 and 10607 ng∙h/mL, respectively, P = 0.001). In multiple regression analyses, the NR1I2 -25385C > T polymorphism (P = 0.001) and female sex (P = 0.002) were independently predictive of a higher asciminib AUC for the 40 mg BID regimen (determination coefficient: 52.8%), whereas body weight (P < 0.001) and female sex (P = 0.047) were independently predictive of a higher asciminib AUC for the 80 mg QD regimen (determination coefficient: 52.2%).

[CONCLUSION] Overall, our findings showed that an adjustment of the initial asciminib dose may be needed based on genotyping information for the NR1I2 -25385C > T polymorphism and the body weight of the patient; however, further prospective studies are necessary.