Monitoring and Improving Adherence to Tyrosine Kinase Inhibitors in Patients with Chronic Myeloid Leukemia: A Systematic Review

Purpose: Suboptimal adherence to tyrosine kinase inhibitors (TKIs) is a widely recognized issue compromising the disease control and survival of patients with chronic myeloid leukemia (CML). A recently published review by Heiney et al reported inconclusive findings on the effects of a broad range of adherence enhancing interventions. The current systematic review aimed to identify studies that evaluated adherence-enhancing interventions implemented by healthcare professionals and determine their effect on CML patients' medication adherence and clinical outcomes. Methods: A systematic literature search was performed in 5 databases for articles published between 2002 and 2021. Studies that compared adherence enhancing interventions implemented by healthcare professionals with a comparison group were included. Relevant data on study characteristics were extracted. Medication adherence and clinical outcomes between intervention and control arms were compared. Results: Nine studies were included in two randomised controlled trials, four cohort studies, and three before-and-after comparison studies. All the included studies incorporated complex interventions, including intensive education or consultation with pharmacists, nurses or multidisciplinary team, in combination with one or more other strategies such as structured follow-up, written materials or video, psychotherapy, medication reminder or treatment diary, with the overall goal of monitoring and improving TKI adherence. Most (7 out of 9) studies demonstrated significantly better adherence to TKIs in the intervention group than the comparison group. The relative proportion of participants who adhered to TKIs ranged from 1.22 to 2.42. The improvement in the rate of TKI doses taken/received ranged from 1.5% to 7.1%. Only one study showed a significant association between intervention and clinical outcomes, with a 22.6% higher major molecular response rate and improvement in 6 out of 20 subscales of health-related quality-of-life. Conclusion: Complex interventions delivered by healthcare professionals showed improvement in adherence to TKIs in CML patients. Further studies are required to clarify the costeffectiveness of adherence-enhancing interventions.