Real world treatment patterns in chronic myeloid leukemia patients newly initiated on tyrosine kinase inhibitors in an U.S. integrated healthcare system

Evaluation of real-world versus clinical trial outcomes of tyrosine kinase inhibitor therapy for chronic myeloid leukemia

Tyrosine kinase inhibitors (TKIs) are the mainstay of treatment for chronic myeloid leukemia (CML). Patients enrolled in clinical trials investigating the safety and efficacy of TKIs in CML are generally younger, have fewer comorbidities, and are monitored differently than patients treated in the real world. This narrative literature review summarizes efficacy outcomes (complete cytogenetic response, major molecular response, and disease progression) and safety outcomes (duration of TKI therapy, TKI discontinuation rates, dosage changes, and frequently reported adverse events) from landmark clinical trials as well as real-world studies. Patients with CML treated with TKIs in a real-world setting may achieve different rates of specific response milestones than those treated on clinical trials. While real-world studies reported similar overall incidences of adverse events as clinical trials, real-world patients with CML were more likely to discontinue TKIs due to adverse events.

Chronic Myeloid Leukemia: Part I-Real-World Treatment Patterns, Healthcare Resource Utilization, and Associated Costs in Later Lines of Therapy in the United States

Background: Despite advances in tyrosine kinase inhibitor (TKI) therapy for chronic myeloid leukemia in chronic phase (CML-CP), a sizeable proportion of patients with CML-CP remains refractory or intolerant to these agents. Objectives: Treatment patterns, healthcare resource utilization (HRU), and costs were evaluated among patients with CML who received third or later lines of therapy (3L+), a clinical population that has not been previously well-studied, with unmet treatment needs as TKI therapy has repeatedly failed. Methods: Adult patients with CML who received 3L+ were identified in the IBM® MarketScan® Databases (January 1, 2001-June 30, 2019) and the SEER-Medicare-linked database (January 1, 2006-December 31, 2016). Treatment patterns were observed from CML diagnosis. HRU and direct healthcare costs (payer's perspective, 2019 USD) were measured in a 3L+ setting. Results: Among 296 commercially insured patients with 3L+ (median age, 58.5 years; female, 49.7%), the median duration of first-line (1L), second-line (2L), and 3L therapy was 8.5, 4.2, and 8.3 months, respectively. The annual incidence rate during 3L+ was 3.4 for inpatient days, 30.8 for days with outpatient services, and 1.2 for emergency department visits. Mean per-patient-per-month (PPPM) total healthcare costs (pharmacy + medical costs) were $18 784 in 3L+, $15 206 in 3L, and $19 546 in 4L, with inpatient costs driving most of the difference between 3L and 4L (mean [3L] = $2528 PPPM, mean [4L] = $6847 PPPM). Among 53 Medicare-insured patients with 3L+ (median age, 72.0 years; female, 39.6%), the median duration of 1L, 2L, and 3L therapy was 9.7, 5.0, and 7.0 months, respectively. During 3L+, the annual incidence rate was 10.3 for inpatient days, 61.9 for days with outpatient services, and 1.5 for emergency department visits. Mean PPPM total healthcare costs were $14 311 in 3L+, $15 100 in 3L, and $16 062 in 4L. Discussion: Patients with CML receiving 3L+ rapidly cycled through multiple lines. Costs increased from 3L to 4L; in commercially insured patients, inpatient costs were responsible for most of the cost increase between 3L and 4L, underlying these patients' continued need for care. Conclusions: These findings support the need for better treatment options in patients with CML undergoing later lines of therapy.

Incidence, Prevalence and Real-World Treatment Patterns in Chronic Myeloid Leukemia: Results from a Population Representative German Claims Data Analysis

Introduction Real-world data on usage of 1st, 2nd and 3rd generation tyrosine kinase inhibitor (TKIs) in chronic myeloid leukemia (CML) is scarce. This study therefore aimed to analyze the use of different TKIs used in 1st- and 2nd-line treatment and the frequency of TKI switches in CML. Methods This observational study was based on the InGef research database, an anonymized representative claims dataset in Germany (n= 4 million). An incidence and prevalence patient CML cohort was followed for 5 and 3 years. Analyses regarding incidence, prevalence and therapy distribution were performed descriptively. Results 151 patients were included in the incidence and 636 patients in the prevalence cohort. This resulted in an incidence of 1.8 (95%-confidence interval [CI]: 1.34 - 2.20) and a prevalence of 14.9 (95%-CI 13.70 - 16.03) per 100,000 inhabitants. For the incidence cohort, data on 1st-line therapy was available for 124 patients and distributed across imatinib (N=52), nilotinib (N=44), dasatinib (N=12), chemotherapies as hydroxycarbamide (N=11) and ponatinib/bosutinib (N=5). 26% of patients switched TKI therapy at least once in three years. In the prevalence cohort, 423 patients (66.5%) had claims on existing or newly emerged cardiovascular diseases (CD). No significant differences (p=0.32) between TKIs in patients with CD were found. Discussion Every fourth patient switched TKI therapy within the first three years after treatment initiation. Switches were more likely when hints of disease progression or intolerability were observable in the database.

Contemporary practice patterns of tyrosine kinase inhibitor use among older patients with chronic myeloid leukemia in the United States

Introduction:

The choice of BCR-ABL1 tyrosine kinase inhibitors (TKI) for the first line of therapy (LOT) for chronic-phase chronic myeloid leukemia (CML) is tailored to disease risk and patient characteristics like comorbidities, which become more prevalent with age. However, contemporary evaluations of frontline TKI choice and the factors associated with TKI switching in this specific patient population are lacking.

Methods:

We sought to describe TKI use in older patients (age: 66–99 years) with CML in the United States. Using the Surveillance, Epidemiology, and End Results–Medicare-linked database, we identified 810 older (median age: 75 years, interquartile range: 70–80 years) patients diagnosed during 2007–2015.

Results:

Imatinib was the most common frontline TKI (63.1%) throughout the study period, but its utilization as such decreased from 76% in 2010 to 47% in 2015. Most patients (65.3%) used only one TKI, but 12.5% of the 281 patients who switched from frontline TKI received ⩾4 LOT. Among the 167 patients switching from frontline imatinib, 18.6% eventually returned to imatinib with nearly all as the third LOT, supporting its favorable safety profile and indicating that the initial switch from imatinib might have been premature. Older patients within our cohort, white patients and those with greater comorbidity were less likely to switch from frontline TKI. Diagnosis year, geographic region, and surrogates for socioeconomic status and healthcare access had no impact on TKI switching.

Conclusion:

As expected, our findings highlight the frequent use of imatinib as the treatment option for older CML patients despite the availability of second-generation TKIs.

The Impact of Urate-Lowering Therapy in Post-Myocardial Infarction Patients: Insights from a Population-Based, Propensity Score-Matched Analysis

The role of urate‐lowering therapy (ULT) for the primary prevention of cardiovascular (CV) events has been widely discussed, but its evidence for the secondary prevention of myocardial infarction (MI) is limited. Therefore, we conduct a population‐based, propensity score‐matched cohort study to investigate the CV outcomes among patients with post‐MI with and without ULT. A total of 19,042 newly diagnosed in‐hospital patients with MI were selected using the Taiwan National Health Insurance Database between January 1, 2005, and December 31, 2016. After 1:1 propensity score matching with covariates, patients with MI with (n = 963) and without (n = 963) ULT were selected for further analysis. The primary outcome was the all‐cause mortality and the secondary outcomes were composite CV outcomes, including hospitalization for recurrent MI, stroke, heart failure, and cardiac arrhythmias. ULT users were associated with lower all‐cause mortality (adjusted hazard ratio (adjHR), 0.67; 95% confidence interval (CI), 0.51–0.87) compared to the ULT nonusers. In addition, ULT users had a significantly lower risk of recurrent MI, which needed revascularization by percutaneous coronary intervention or coronary artery bypass grafting (adjHR, 0.67; 95% CI, 0.53–0.86) than the ULT nonusers. The primary and secondary outcomes were not different between patients with post‐MI who received uricosuric agents and xanthine oxidase inhibitors. The anti‐inflammatory effect of ULT plays an essential role in MI management. From a real‐world setting, this study shows that ULT is associated with the lower risk of all‐cause mortality in patients with post‐MI. In addition, the result shows the possible lower incidence of repeat revascularization procedures in the ULT users.

Long-Term Patterns of Oral Anticancer Agent Adoption, Duration, and Switching in Patients With CML

BACKGROUND

Oral tyrosine kinase inhibitors (TKIs) have been the standard of care for chronic myeloid leukemia (CML) since 2001. However, few studies have evaluated changes in the treatment landscape of CML over time. This study assessed the long-term treatment patterns of oral anticancer therapies among patients with CML.

METHODS

This retrospective cohort study included patients newly diagnosed with CML between January 1, 2000, and December 31, 2016, from 10 integrated healthcare systems. The proportion of patients treated with 5 FDA-approved oral TKI agents-bosutinib, dasatinib, imatinib, nilotinib, and ponatinib-in the 12 months after diagnosis were measured, overall and by year, between 2000 and 2017. We assessed the use of each oral agent through the fourth-line setting. Multivariable logistic regression estimated the odds of receiving any oral agent, adjusting for sociodemographic and clinical characteristics.

RESULTS

Among 853 patients with CML, 81% received an oral agent between 2000 and 2017. Use of non-oral therapies decreased from 100% in 2000 to 5% in 2005, coinciding with imatinib uptake from 65% in 2001 to 98% in 2005. Approximately 28% of patients switched to a second-line agent, 9% switched to a third-line agent, and 2% switched to a fourth-line agent. Adjusted analysis showed that age at diagnosis, year of diagnosis, and comorbidity burden were statistically significantly associated with odds of receiving an oral agent.

CONCLUSIONS

A dramatic shift was seen in CML treatments away from traditional, nonoral chemotherapy toward use of novel oral TKIs between 2000 and 2017. As the costs of oral anticancer agents reach new highs, studies assessing the long-term health and financial outcomes among patients with CML are warranted.