Clinical Edge Journal Scan Commentary: CML December 2021

Patients who adhere to their tyrosine kinase inhibitor (TKI) medication regimen will achieve CML survival goals that would be expected for their age group. Imatinib is a first generation TKI inhibitor.  In a recent post hoc analysis of the ADAGIO study patients, Obeng-Kusi M et al¹ showed that compared with 90% adherence, a 100% adherence to imatinib was associated with a 2-fold increase in achieving or maintaining treatment response in patients with chronic myeloid leukemia (CML), highlighting the urgent need to assess and promote patient adherence. There is virtually no margin for nonadherence, if the objective is to optimize the likelihood of treatment response, and a minimal margin to avoid impaired treatment response.

On the same topic, Davis TC et al.²also recently reported a study of suboptimal adherence to TKI. From the 86 patients with CML studied, almost 17.9% of participants reported nonadherence, i.e., missing at least 1 dose of CML medication in the previous week. The main reason that patients reported nonadherence were side effects, a busy schedule, and the difficulty of complying daily with the TKI regimen.

Cardiovascular adverse events (AE) have been described with TKI treatment at different rates, but cardiovascular risk stratification was not included in the design of many trials. Baggio D et al³  in a retrospective study included 88 patients with CML treated with any TKI and a median follow up of 3.8 months. They described the rates of major cardiovascular AEs by combining age, history of prior cardiovascular diseases, and Framingham risk score, along with additional insights from coronary artery calcium scoring (CACS). The authors found cardiovascular AEs in 0%, 10%, and 19%, of the low-, intermediate-, and high-risk groups respectively. By using CACS score they were able to reclassify patients from intermediate to low risk and none of those patients experienced a major adverse cardiovascular event.

The use of kinase domain mutation analysis at diagnosis is not a recommended practice by the National Comprehensive Cancer Network (NCCN) or the European Leukemia Net (ELN), but is reserved for use in patents who failed first or subsequent lines of therapies. Furthermore, previous publications in the topic have showed discordant results. More recently, the use of ultra-deep sequencing has detected low-frequency genetic mutations with high sensitivity. Park H et al.⁴ recently described the most common mutations found in a population of 50 CML patients treated with nilotinib. V299 L mutation associated with dasatinib resistance and nilotinib sensitivity were observed in 98% of patients. Two uncommon mutations S417Y and the V371A were associated with reduced molecular response.

References

1. Obeng-Kusi M et al. No margin for non-adherence: Probabilistic Kaplan-Meier modeling of imatinib non-adherence and treatment response in CML (ADAGIO study). Leuk Res. 2021;111:106734 (Oct 21).
2. Davis TC et al. Assessment of oral chemotherapy nonadherence in chronic myeloid leukemia patients using brief measures in community cancer clinics: a pilot study. Int J Environ Res Public Health. 2021;18(21):11045 (Oct 21).
3. Baggio D et al. Prediction of cardiovascular events in patients with chronic myeloid leukaemia using baseline risk factors and coronary artery calcium scoring. Intern Med J. 2021;51(10):1736-40 (Oct 18).  
4. Park H et al. Ultra-deep sequencing mutation analysis of the BCR/ABL1 kinase domain in newly diagnosed chronic myeloid leukemia patients. Leuk Res. 2021;111:106728 (Oct 15).

Patients who adhere to their tyrosine kinase inhibitor (TKI) medication regimen will achieve CML survival goals that would be expected for their age group. Imatinib is a first generation TKI inhibitor.  In a recent post hoc analysis of the ADAGIO study patients, Obeng-Kusi M et al¹ showed that compared with 90% adherence, a 100% adherence to imatinib was associated with a 2-fold increase in achieving or maintaining treatment response in patients with chronic myeloid leukemia (CML), highlighting the urgent need to assess and promote patient adherence. There is virtually no margin for nonadherence, if the objective is to optimize the likelihood of treatment response, and a minimal margin to avoid impaired treatment response.

On the same topic, Davis TC et al.²also recently reported a study of suboptimal adherence to TKI. From the 86 patients with CML studied, almost 17.9% of participants reported nonadherence, i.e., missing at least 1 dose of CML medication in the previous week. The main reason that patients reported nonadherence were side effects, a busy schedule, and the difficulty of complying daily with the TKI regimen.

Cardiovascular adverse events (AE) have been described with TKI treatment at different rates, but cardiovascular risk stratification was not included in the design of many trials. Baggio D et al³  in a retrospective study included 88 patients with CML treated with any TKI and a median follow up of 3.8 months. They described the rates of major cardiovascular AEs by combining age, history of prior cardiovascular diseases, and Framingham risk score, along with additional insights from coronary artery calcium scoring (CACS). The authors found cardiovascular AEs in 0%, 10%, and 19%, of the low-, intermediate-, and high-risk groups respectively. By using CACS score they were able to reclassify patients from intermediate to low risk and none of those patients experienced a major adverse cardiovascular event.

The use of kinase domain mutation analysis at diagnosis is not a recommended practice by the National Comprehensive Cancer Network (NCCN) or the European Leukemia Net (ELN), but is reserved for use in patents who failed first or subsequent lines of therapies. Furthermore, previous publications in the topic have showed discordant results. More recently, the use of ultra-deep sequencing has detected low-frequency genetic mutations with high sensitivity. Park H et al.⁴ recently described the most common mutations found in a population of 50 CML patients treated with nilotinib. V299 L mutation associated with dasatinib resistance and nilotinib sensitivity were observed in 98% of patients. Two uncommon mutations S417Y and the V371A were associated with reduced molecular response.

References

1. Obeng-Kusi M et al. No margin for non-adherence: Probabilistic Kaplan-Meier modeling of imatinib non-adherence and treatment response in CML (ADAGIO study). Leuk Res. 2021;111:106734 (Oct 21).
2. Davis TC et al. Assessment of oral chemotherapy nonadherence in chronic myeloid leukemia patients using brief measures in community cancer clinics: a pilot study. Int J Environ Res Public Health. 2021;18(21):11045 (Oct 21).
3. Baggio D et al. Prediction of cardiovascular events in patients with chronic myeloid leukaemia using baseline risk factors and coronary artery calcium scoring. Intern Med J. 2021;51(10):1736-40 (Oct 18).  
4. Park H et al. Ultra-deep sequencing mutation analysis of the BCR/ABL1 kinase domain in newly diagnosed chronic myeloid leukemia patients. Leuk Res. 2021;111:106728 (Oct 15).

Patients who adhere to their tyrosine kinase inhibitor (TKI) medication regimen will achieve CML survival goals that would be expected for their age group. Imatinib is a first generation TKI inhibitor.  In a recent post hoc analysis of the ADAGIO study patients, Obeng-Kusi M et al¹ showed that compared with 90% adherence, a 100% adherence to imatinib was associated with a 2-fold increase in achieving or maintaining treatment response in patients with chronic myeloid leukemia (CML), highlighting the urgent need to assess and promote patient adherence. There is virtually no margin for nonadherence, if the objective is to optimize the likelihood of treatment response, and a minimal margin to avoid impaired treatment response.

On the same topic, Davis TC et al.²also recently reported a study of suboptimal adherence to TKI. From the 86 patients with CML studied, almost 17.9% of participants reported nonadherence, i.e., missing at least 1 dose of CML medication in the previous week. The main reason that patients reported nonadherence were side effects, a busy schedule, and the difficulty of complying daily with the TKI regimen.

Cardiovascular adverse events (AE) have been described with TKI treatment at different rates, but cardiovascular risk stratification was not included in the design of many trials. Baggio D et al³  in a retrospective study included 88 patients with CML treated with any TKI and a median follow up of 3.8 months. They described the rates of major cardiovascular AEs by combining age, history of prior cardiovascular diseases, and Framingham risk score, along with additional insights from coronary artery calcium scoring (CACS). The authors found cardiovascular AEs in 0%, 10%, and 19%, of the low-, intermediate-, and high-risk groups respectively. By using CACS score they were able to reclassify patients from intermediate to low risk and none of those patients experienced a major adverse cardiovascular event.

The use of kinase domain mutation analysis at diagnosis is not a recommended practice by the National Comprehensive Cancer Network (NCCN) or the European Leukemia Net (ELN), but is reserved for use in patents who failed first or subsequent lines of therapies. Furthermore, previous publications in the topic have showed discordant results. More recently, the use of ultra-deep sequencing has detected low-frequency genetic mutations with high sensitivity. Park H et al.⁴ recently described the most common mutations found in a population of 50 CML patients treated with nilotinib. V299 L mutation associated with dasatinib resistance and nilotinib sensitivity were observed in 98% of patients. Two uncommon mutations S417Y and the V371A were associated with reduced molecular response.

References

1. Obeng-Kusi M et al. No margin for non-adherence: Probabilistic Kaplan-Meier modeling of imatinib non-adherence and treatment response in CML (ADAGIO study). Leuk Res. 2021;111:106734 (Oct 21).
2. Davis TC et al. Assessment of oral chemotherapy nonadherence in chronic myeloid leukemia patients using brief measures in community cancer clinics: a pilot study. Int J Environ Res Public Health. 2021;18(21):11045 (Oct 21).
3. Baggio D et al. Prediction of cardiovascular events in patients with chronic myeloid leukaemia using baseline risk factors and coronary artery calcium scoring. Intern Med J. 2021;51(10):1736-40 (Oct 18).  
4. Park H et al. Ultra-deep sequencing mutation analysis of the BCR/ABL1 kinase domain in newly diagnosed chronic myeloid leukemia patients. Leuk Res. 2021;111:106728 (Oct 15).