•  
  •  
 

The Thai Journal of Pharmaceutical Sciences

Abstract

Background: In Thailand, imatinib (IMT) is used as the first-line therapy for all risk scores of chronic myeloid leukemia (CML). IMT is typically effective but is only recommended for lowrisk CML in the international recommendations to treat CML. Consequently, the response rate of IMT may vary for patients with intermediate-to-high risk CML. Notably, the response rate of IMT in Thailand remains limited. Objectives: This retrospective study aimed to determine the response rate of IMT and the response rate when stratified by risk for CML treatment in Thailand. Materials and Methods: Patients with newly diagnosed CML treated with IMT as the initial therapy at Maharaj Nakorn Chiang Mai Hospital or Lampang Hospital between January 1, 2011, and April 30, 2019, were included. The primary endpoint was the response rate, determined as the complete hematologic response rate (CHR) at 3 months, the early molecular response rate (EMR) at 6 months, or the major molecular response rate (MMR) at 12 and 18 months. The secondary endpoint was progression-free survival (PFS). The prognostic risk scores were calculated according to Sokal risk, the Hasford score, the European treatment outcome study (EUTOS), and the EUTOS long-term survival (ELTS). Results: Of 225 patients with CML, the average age was 48.0 ± 16.6 years, and the majority were male (56.4%). The response rates were relatively high when CHR at 3 months was 81.4%, EMR at 6 months was 55.8%, MMR at 12 months was 58.7%, and MMR at 18 months was 69.5%. The median of PFS in all samples was 81.4 ± 6.7 months (95% CI: 62.8–101.7). Only 195 patients (86.7%) had sufficient information for the risk score calculation. According to various prognostic risks, most patients were diagnosed with high risk for Sokal score at 38.0%, intermediate risk for Hasford score at 47.2%, low risk for EUTOS score at 68.2%, and high risk for ELTS score at 45.6%. However, MMR at 18 months among different prognostic risks in various risk classifications showed slightly differ across risk scores, without statistical significance. Conclusion: Thai CML patients with various prognostic risks respond well to IMT. Thus, the use of IMT, regardless of the risk classification, is acceptable in Thailand.

Download

Share

COinS