Influence of CYP2C8*3 and ABCG2 C421A genetic polymorphisms on trough concentration and molecular response of imatinib in Egyptian patients with chronic myeloid leukemia

The treatment landscape for chronic myeloid leukemia (CML) has been revolutionized by the introduction of imatinib, a tyrosine kinase inhibitor, which has transformed the disease from a fatal condition into a manageable chronic illness for a substantial number of patients. Despite this, some individuals do not respond adequately to the treatment, and others may experience disease progression even with continued therapy. This study examined how CYP2C8*3 (G416A; rs11572080) and ABCG2 C421A (rs2231142) single nucleotide polymorphisms (SNPs) affect the plasma trough concentration and therapeutic response of imatinib in Egyptian CML patients.

The study included fifty patients with chronic-phase CML, who were categorized into two groups: responders (n = 26) and non-responders (n = 24), according to their BCR-ABL1 transcription levels after 12 months of imatinib treatment. Genotyping of the CYP2C8*3 and ABCG2 C421A polymorphisms was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), while plasma trough concentrations were determined through high-performance liquid chromatography with ultraviolet-diode array detection (HPLC-UV/DAD).

Patients with the CA genotype of ABCG2 C421A showed significantly higher mean plasma trough concentrations of imatinib (CA: 1731 ± 424.7 ng/mL; CC: 1294 ± 381.3 ng/mL; p = 0.0132) and demonstrated a better molecular response compared to those with the CC genotype (p = 0.0395).