Change of health-related profiles after Imatinib cessation in chronic phase chronic myeloid leukemia patients

De-escalation or discontinuation of tyrosine kinase inhibitor in patients with chronic myeloid leukemia: A multicentral, open-label, prospective trial in China

Background: Long-term treatment-free remission (TFR) represents a new goal for chronic myeloid leukemia (CML). Optimizing dose of tyrosine kinase inhibitors (TKIs) in the CML treatment maybe a new challenge to maintain effective and improving patients' quality of life. We hypothesized that administration of low-dose TKIs does not compromise major molecular response (MMR) in patients with CML who have a deep molecular response (DMR). Methods: We did an open-label, randomized trial at eight hospitals in China. Eligible CML-CP patients (aged 18-70 years) had shown continuous response to TKI more than 5 years and maintained MR4.5 (BCR-ABLIS ≤ 0.0032%) in recent 18 months. Patients were randomly assigned (1:1) to the TKI de-escalation group or the discontinuation group. Randomization was done with permuted blocks (block size four) and implemented through an interactive web-based randomization system. Recurrence was defined as the single sample with real time Quantitative PCR (RT-qPCR) measurement greater than 0.1% (MMR). The primary endpoint was 12-month MMR rate in patients who received de-escalation or discontinuation of TKIs. This study was registered at ClinicalTrials.gov (NCT04143087). Results: Around 125 patients were enrolled between October 23, 2019 and October 31, 2020, 62 patients received dose de-escalation of TKIs, while 63 patients in the discontinuation group. In the de-escalation group, molecular recurrence-free survival at 12 months was 88.32% (95% CI 79%-98%), whereas molecular recurrence-free survival in the discontinuation group at 12 months was 59.98% (95% CI 47-73). No progressions occurred at the data cut-off date. All 29 recurrence cases restart TKI treatment returned to MMR. Cytolytic NK cells as a proportion of lymphocyte cells were significantly increased from baseline after 6 months whether in the de-escalation or TKIs cessation group (P = 0.048, 0.001, respectively); compared with the relapsing patients, Tregs proportion was decreased (P = 0.003), and higher proportion of NK cells were found in non-relapsing patients whether in TKI de-escalation or discontinuation group (P = 0.011, 0.007, respectively). We also found that the de-escalation group showed better disease-specific HRQOL in regards to its impact on emotional functioning, fatigue, pain, and financial difficulties. Conclusion: With 88.32% MMR in 12-months follow-up after de-escalation TKIs' treatment, dose-halving could become a new treatment paradigm for CML patients who with DMR under continuing maintenance therapy with TKIs.

Withdrawal syndrome after tyrosine kinase inhibitors discontinuation in patients with chronic myeloid leukemia

Background. Withdrawal syndrome (WS) a musculoskeletal pain after discontinuation of tyrosine kinase inhibitors (TKI) in patients with chronic myeloid leukemia (CML) has been described in the treatment-free remission (TFR) studies. The pathophysiological mechanisms and predisposing factors of WS have not been well established. Aim. Our aim was to evaluate clinical features and factors associated with WS in the Russian cohort of CML patients who discontinued TKI therapy. Materials and methods. WS was evaluated in total of 183 CML patients with chronic phase and sustained deep molecular response (DMR). WS was defined as a musculoskeletal pain newly observed after TKI cessation or as a worsening of previously observed symptoms. Results. DMR loss free survival at 36 months was 49% and 43% in prospective and retrospective groups respectively (p=0.96) with mеdian (Me) time of observation 33 months (range 1136). WS was observed in 49 (27%) patients: grade 12 was in 45 (92%) patients, grade 3 in 4 (8%) patients. Me time to WS occurrence was 2 months (range 17), Ме duration of WS was 5 months (range 135). WS was resolved in 14 of 15 patients with molecular relapse after 13 months of TKI re-initiation and was decreased in 1 patient. WS was completely resolved in 31 of 34 patients who continued remained in TFR and decreased in 3 patients. WS was resolved spontaneously or with nonsteroidal anti-inflammatory drugs in 14 (45%) and 17 (55%) patients accordingly. Older age (p0.0001), longer duration of TKI therapy (p0.0001) and presence of locomotion system diseases (p=0.022) were observed in patients with WS. No WS was observed in pregnant patients (р0.001). Survival without DMR loss at 12 months after TKI stop was 66 and 42% in patients with and without WS accordingly (р=0.095). Conclusion. The rate of WS was 27% that is in a good concordance with the data of the other TFR studies. A longer period of TKI exposure, older age and the history of locomotion system diseases were associated with the development of the WS. We found for the first time that WS was not observed in patients with pregnancy. There was no association of WS development and the rate of molecular relapses.

Discontinuation of tyrosine kinase inhibitors in pediatric chronic myeloid leukemia

BACKGROUND

The feasibility of tyrosine kinase inhibitor (TKI) discontinuation in pediatric chronic myeloid leukemia (CML) remains to be fully elucidated.

PROCEDURES

TKI was prospectively discontinued in patients who were diagnosed with CML at <20 years of age, treated with TKI for ≥3 years, and sustained molecular response 4.0 (MR4.0) for ≥2 years. Molecular relapse was defined as a single loss of major molecular response (MMR) (BCR-ABL1^IS >0.1%). Relapsed patients resumed the same TKI therapy administered before discontinuation.

RESULTS

Twenty-two patients with chronic-phase CML were enrolled, and the median ages at diagnosis and at TKI discontinuation were 9 (range: 1-14) years and 16 (5-26) years, respectively. The median follow-up time after TKI discontinuation was 37 months (range: 24-41 months). The median duration of TKI treatment before discontinuation was 100 (42-178) months, and that of MR4.0 was 53.5 (25-148) months. The treatment-free remission (TFR) rate at 12 months was 50.0% (90% confidence interval: 31.7%-65.8%). Eleven patients experienced loss of MMR within 4 months after TKI discontinuation and resumed TKI as originally prescribed. No progression was observed, and all 11 patients regained MR4.0 after TKI resumption. No patient had a withdrawal syndrome. The quality-of-life analysis suggested that successful TFR may improve academic performance in some patients. In patients who discontinued TKI therapy before puberty, the possibility of improvement in growth velocity upon TKI discontinuation was observed.

CONCLUSIONS

TKI could be discontinued safely in patients with pediatric CML showing a sustained deep MR.

Health-Related Quality of Life of Patients with Chronic Myeloid Leukemia as Measured by Patient-Reported Outcomes: Current State and Future Directions

PURPOSE OF REVIEW

Tyrosine kinase inhibitors (TKIs) allow many patients with chronic myeloid leukemia (CML) to live normal life spans but have the potential to impact patients' health-related quality of life (HRQOL). Patient-reported outcome (PRO) measures can provide valuable information to inform treatment decision-making. Here, we review pivotal studies that used PRO measures to evaluate HRQOL of patients with CML in the first-line and treatment-free remission (TFR), and identify areas for future research.

RECENT FINDINGS

PRO measures commonly studied in patients with CML include the SF-36, FACT-Leu, EORTC QLQ-CML24, and MDASI CML. Cohort or cross-sectional studies provide the most data on PRO measures in patients with CML, with less information available from randomized controlled trials (RCTs). Patients with CML taking TKIs have worse HRQOL compared to matched controls, with a few studies seeing a larger effect in younger patients (< 60 years old). No single TKI consistently has better HRQOL compared to other agents. Fatigue is a predominant symptom associated with impaired HRQOL across many studies. Studies evaluating TFR show stable or improved HRQOL after TKI discontinuation. There are areas of HRQOL detrimental to patients with other types of cancer (e.g., cognition, sexuality) that warrant further evaluation in patients with CML. Understanding the HRQOL of patients with CML is increasingly important as patients live near-normal life expectancies. PRO measures have the potential to inform treatment decisions in this patient population. Future research opportunities include using PRO measures in RCTs and expanding the HRQOL topics studied in patients with CML.

Management of Adverse Events Associated With Tyrosine Kinase Inhibitor Use in Adult Patients With Chronic Myeloid Leukemia in Chronic Phase: An Advanced Practice Perspective

The tyrosine kinase inhibitors (TKIs) imatinib, dasatinib, nilotinib, bosutinib, and ponatinib have drastically improved the life expectancies of patients with chronic myeloid leukemia in chronic phase (CML-CP). While survival outcomes are comparable across first-line TKIs, each TKI has a unique toxicity profile that should be considered before starting or managing any treatment. Furthermore, the safety and tolerability of TKIs are particularly important in CML-CP, as the majority of patients remain on treatment for several years or for life. Management of adverse events (AEs) is critical to ensure adherence to treatment and to maintain efficacy and quality of life; management should also be considered in the context of the patient's molecular response to therapy to avoid switching TKIs unnecessarily. We present case studies examining pleural effusion occurring with bosutinib and dasatinib, cardiovascular events associated with nilotinib and ponatinib, and myelosuppression, which is common across all TKIs. We discuss the management of these AEs based on international guidelines and present our collective experience for advanced practitioners to consider.

Budget Impact of Tyrosine Kinase Inhibitor Discontinuation in Chronic Myeloid Leukemia With Sustained Deep Molecular Response

OBJECTIVES

Tyrosine kinase inhibitors (TKIs) account for the vast majority of healthcare expenditure on patients with chronic myeloid leukemia (CML), and it has been demonstrated that TKI discontinuation in patients in long-term deep molecular remission (DMR) is safe and improves quality of life. Our objective was to estimate the budget impact of TKI discontinuation in CML patients in long-term DMR from the perspective of the French healthcare system.

METHODS

This analysis was conducted over a 5-year time horizon using a Markov model with cycles of 6 months. Transition probabilities were estimated through systematic reviews and meta-analyses. Costs were estimated from the French National Claims Database. Monte Carlo simulations were performed to take into account the uncertainty surrounding model parameters. Sensitivity analyses were carried out by varying the size of the target population and the cost of TKIs.

RESULTS

Over a 5-year period and for a target population of 100 patients each year eligible and agreeing to stop TKI, the TKI discontinuation strategy would save €25.5 million (95% confidence interval -39.3 to 70.0). In this model, the probability that TKI discontinuation would be more expensive than TKI continuation was 12.0%. In sensitivity analyses, mean savings ranged from €14.9 million to €62.9 million.

CONCLUSIONS

This study provides transparent, reproducible, and interpretable results for healthcare professionals and policy makers. Our results clearly show that innovative healthcare strategies can benefit both the healthcare system and patients. Savings from generalizing TKI discontinuation in CML patients in sustained DMR should yield health gains for other patients.

Health state utility and quality of life measures in patients with chronic myeloid leukemia in France

PURPOSE

Tyrosine kinase inhibitors (TKIs) have dramatically improved the prognosis of chronic myeloid leukemia (CML). We aimed to assess health state utility and quality of life (QoL) in French patients with CML in real-life setting, to study the determinants of utility score and to compare health-related QoL values to general population norms.

METHODS

We conducted a cross-sectional study in 412 patients with CML. Data were collected by electronic survey. Three patient-reported outcomes questionnaires were used: EORTC QLQ-C30, EORTC QLQ-CML24 and EuroQol EQ-5D-3L. Health state utility values were computed using the French value set. We computed deviations from reference norms from the general population. We studied the determinants of health utility score using multiple regression models.

RESULTS

The mean utility score (SD) was 0.72 (0.25) in the chronic phase and 0.84 (0.21) in treatment-free remission, with marked variations by gender. Patients with CML had a deviation from the reference norm of -0.15 on average (SD: 0.25). In terms of QoL, social functioning, role functioning and cognitive functioning were notably impacted with a mean difference of -16.0, -13.1 and -11.7 respectively. Fatigue, dyspnea and pain were the symptoms with the highest deviation from general population norms (mean difference of 20.6, 14.0 and 8.3 respectively). In the multiple regression analysis, fatigue was the most important independent predictor of the utility score.

CONCLUSION

Although TKIs prevent the disease from progressing and even allow remission without treatment, QoL in patients with CML is notably altered. The utility scores deteriorate with CML symptoms.

Predictive indicators of successful tyrosine kinase inhibitor discontinuation in patients with chronic myeloid leukemia

Clinical trials have demonstrated that some patients with chronic myeloid leukemia (CML) treated for several years with tyrosine kinase inhibitors (TKIs) who have maintained a molecular response can successfully discontinue treatment without relapsing. Treatment free remission (TFR) can be reached by approximately 50% of patients who discontinue. Despite having similar levels of deep molecular response and an identical duration of treatment, the factors that influence the successful discontinuation of CML patients remain to be determined. In this review we will explore the factors identified to date that can help predict whether a patient will successfully achieve TFR. We will also discuss the need for the identification of predictive biomarkers associated with a high probability of achieving TFR for the future personalized identification of patients who are suitable for the discontinuation of TKI treatment.

Handling challenging questions in the management of chronic myeloid leukemia: when is it safe to stop tyrosine kinase inhibitors?

The paradigm for managing patients with chronic myeloid leukemia is evolving. In the recent past, restoring a normal life expectancy while patients are receiving never-ending targeted therapy with BCR-ABL1 tyrosine kinase inhibitors through prevention of progression to blast phase and mitigation of iatrogenic risks was considered the best achievable outcome. Now, long-term treatment-free remission with continued response off tyrosine kinase inhibitor therapy is recognized as the most optimal benefit of treatment. Indeed, numerous independent clinical trials provided solid proof that tyrosine kinase inhibitor discontinuation was feasible in patients with deep and sustained molecular responses. This article discusses when tyrosine kinase inhibitors may be safely stopped in clinical practice on the basis of the best and latest available evidence.

Handling challenging questions in the management of chronic myeloid leukemia: when is it safe to stop tyrosine kinase inhibitors?

The paradigm for managing patients with chronic myeloid leukemia is evolving. In the recent past, restoring a normal life expectancy while patients are receiving never-ending targeted therapy with BCR-ABL1 tyrosine kinase inhibitors through prevention of progression to blast phase and mitigation of iatrogenic risks was considered the best achievable outcome. Now, long-term treatment-free remission with continued response off tyrosine kinase inhibitor therapy is recognized as the most optimal benefit of treatment. Indeed, numerous independent clinical trials provided solid proof that tyrosine kinase inhibitor discontinuation was feasible in patients with deep and sustained molecular responses. This article discusses when tyrosine kinase inhibitors may be safely stopped in clinical practice on the basis of the best and latest available evidence.

Muscle Toxicity of Drugs: When Drugs Turn Physiology into Pathophysiology

Drugs are prescribed to manage or prevent symptoms and diseases, but may sometimes cause unexpected toxicity to muscles. The symptomatology and clinical manifestations of the myotoxic reaction can vary significantly between drugs and between patients on the same drug. This poses a challenge on how to recognize and prevent the occurrence of drug-induced muscle toxicity. The key to appropriate management of myotoxicity is prompt recognition that symptoms of patients may be drug related and to be aware that inter-individual differences in susceptibility to drug-induced toxicity exist. The most prevalent and well-documented drug class with unintended myotoxicity are the statins, but even today new classes of drugs with unintended myotoxicity are being discovered. This review will start off by explaining the principles of drug-induced myotoxicity and the different terminologies used to distinguish between grades of toxicity. The main part of the review will focus on the most important pathogenic mechanisms by which drugs can cause muscle toxicity, which will be exemplified by drugs with high risk of muscle toxicity. This will be done by providing information on key clinical and laboratory aspects, muscle electromyography patterns and biopsy results, and pathological mechanism and management for a specific drug from each pathogenic classification. In addition, rather new classes of drugs with unintended myotoxicity will be highlighted. Furthermore, we will explain why it is so difficult to diagnose drug-induced myotoxicity, and which tests can be used as a diagnostic aid. Lastly, a brief description will be given of how to manage and treat drug-induced myotoxicity.

Longer treatment duration and history of osteoarticular symptoms predispose to tyrosine kinase inhibitor withdrawal syndrome

The effectiveness of tyrosine kinase inhibitors (TKIs) has made it possible to consider treatment discontinuation in chronic myeloid leukaemia (CML) patients that achieve an excellent response. However, a few of the patients included in the Europe Stop Tyrosine Kinase Inhibitors (EURO-SKI) trial reported musculoskeletal pain shortly after stopping TKIs, considered as a withdrawal syndrome (WS). To identify factors that may predispose to TKI WS, we analysed the pharmacovigilance declarations for the 6 months after stopping TKIs in a large cohort of CML (n = 427) that combined the French patients included in the STop IMatinib 2 (STIM2; n = 224) and EURO-SKI (n = 203) trials. Among these patients, 23% (99/427) developed TKI WS after stopping imatinib (77/373; 20·4%), nilotinib (12/29; 41·4%) or dasatinib (10/25; 40%). WS concerned mainly the upper body joints, and required multiple symptomatic treatments in 30% of patients. Univariate and multivariate analyses identified two risk factors: duration of TKI treatment [risk ratio (RR) = 1·68 (1·02-2·74)] with a 93-month cut-off time, and history of osteoarticular symptoms [RR = 1·84 (1·04-3·28)]. These findings confirm that WS is a TKI class effect. CML patients should be carefully screened before treatment initiation to identify pre-existent osteoarticular symptoms. Moreover, before TKI discontinuation, patients should be informed of the possibility of WS, particularly after a long treatment period.

Feasibility of treatment discontinuation in chronic myeloid leukemia in clinical practice: results from a nationwide series of 236 patients

Over half of chronic myeloid leukemia (CML) patients in deep molecular response do not lose the major molecular response (MMR) after stopping treatment with tyrosine kinase inhibitors (TKI). This strategy is safe in clinical trials, but its applicability in the real-life setting remains unsettled. We describe the outcomes after TKI discontinuation in a nationwide series of 236 CML patients. Median follow-up from treatment discontinuation was 21.5 months and 5 patients died from CML-unrelated causes. TKI therapy was reinitiated due to MMR loss (n = 52), increase ≥ 1 log in BCR-ABL transcript level without losing MMR (n = 12), patient preference (n = 2), and withdrawal syndrome (n = 1). Treatment-free remission rate at 4 years was 64% (95% confidence interval, CI: 55%–72%). Cumulative incidence of molecular recurrence at 3 years was 33% (95% CI: 26%–38%). TKI treatment for < 5 years and MR4.5 duration shorter than 4 years were both associated with higher incidence of molecular recurrence. No patient had disease progression. Response status at last control was: MR4.5 (n = 196), MR4 (n = 15), MMR (n = 14), complete cytogenetic response (n = 10), and other (n = 1). A significant increase in Hb and cholesterol levels was observed after imatinib withdrawal. Our results demonstrate that TKI treatment discontinuation is feasible in real-life clinical practice.

Considerations for Treatment-free Remission in Patients With Chronic Myeloid Leukemia: A Joint Patient-Physician Perspective

Treatment-free remission (TFR) after discontinuation of tyrosine kinase inhibitor therapy is now an emerging treatment goal for patients with chronic myeloid leukemia, who have achieved a deep and stable response to treatment. Although guidance is now available, patients' questions regarding this progressive concept have yet to be addressed. The overall aim of this European Steering Group is a patient-centered approach that educates patients on their treatment options, including TFR, facilitates better patient-physician relationships, and meets patients' emotional and psychological needs. The present report outlines 5 key topic areas on discontinuing tyrosine kinase therapy and the implications of TFR for patient-physician consideration: what TFR is; when TFR is appropriate; which patients might and might not be eligible for TFR; and patients' considerations for discontinuing therapy, such as tyrosine kinase withdrawal syndrome, potential psychological implications, molecular recurrence, and repeat treatment. This Steering Group advocates that patients with chronic myeloid leukemia should have access to high-quality, frequent molecular monitoring and be treated in a specialist center with appropriate medical and psychological support. As patient concerns with attempting TFR become forefront in patient-physician discussions, a greater number of eligible patients might be willing to discontinue therapy.

Considerations for Successful Treatment-free Remission in Chronic Myeloid Leukemia

BCR-ABL1 tyrosine kinase inhibitors have dramatically improved outcomes for patients with chronic myeloid leukemia, and current studies are investigating whether some patients may be able to suspend therapy yet maintain response in a state known as "treatment-free remission" (TFR). Results from ongoing studies suggest that ≈ 40% to 60% of patients in sustained (generally ≥ 2 years) deep molecular response (defined as a 4-log or deeper reduction in BCR-ABL1 transcripts, depending on the study) who attempt TFR may successfully remain off treatment. Results from TFR clinical trials, patient considerations for attempting TFR, and potential predictive factors associated with successful TFR are reviewed herein.

Higher out-of-pocket expenses for tyrosine kinase-inhibitor therapy is associated with worse health-related quality-of-life in persons with chronic myeloid leukemia

PURPOSE

To explore health-related quality-of-life (HRQoL) profiles and identify socio-demographic and clinical variables associated with HRQoL in persons with chronic myeloid leukemia (CML) receiving tyrosine kinase inhibitors (TKIs).

METHODS

A cross-sectional questionnaire was distributed to adults with chronic-phase CML receiving tyrosine kinase-inhibitor (TKI) therapy >3 months in complete cytogenetic response (CCyR). Respondents were anonymous. SF-36 Health Survey was used to measure HRQoL.

RESULTS

Data from 828 respondents were analyzable. 524 (63%) were male. Median age was 42 years (range 18-88 years). 648 (78%) were receiving imatinib. Median TKI-therapy duration was 36 months (range 3-178 months). 638 (77%) paid some or all of their TKI costs. Annual out-of-pocket expenses >$4600 USD was associated with lower physical component summary (PCS; -2.8 to -3.8; P = 0.0081 and 0.0009) and mental component summary (MCS; -2.1 to -4.3; P = 0.0394 and 0.0080) in multivariate analyses. Other variables significantly associated with a lower PCS and/or MCS included: (1) female sex; (2) increasing age; (3) education level < bachelor degree; (4) co-morbidity(ies); and (5) generic drug use. TKI-therapy duration 3-5 years was associated with higher PCS and MCS.

CONCLUSIONS

Higher out-of-pocket expense for TKI therapy is significantly associated with worse HRQoL in persons with chronic-phase CML in CCyR receiving TKI therapy. These data indicate the importance of drug cost and health insurance policies on people's HRQoL.

Treatment-free remission in patients with chronic myeloid leukemia

Clinical trials have formally demonstrated that in chronic myeloid leukemia (CML), patients treated with tyrosine kinase inhibitors (TKI) who achieved and maintained deep molecular responses could discontinue their treatment after several years without facing overt signs of disease relapse in approximately 50% of the cases. In patients with a molecular relapse, prompt re-introduction of TKI therapy was able to rapidly restore deep molecular responses. The concept of a lifelong therapy with TKI has thus been challenged and treatment-free remission (TFR) strategies will soon integrate clinical practice, providing that safe recommendations will be established. In this article, we give an update on TKI discontinuation studies in CML and we also provide an overview of upcoming TFR clinical and biological challenges.

Natural killer-cell counts are associated with molecular relapse-free survival after imatinib discontinuation in chronic myeloid leukemia: the IMMUNOSTIM study

Despite persistence of leukemic stem cells, patients with chronic myeloid leukemia who achieve and maintain deep molecular responses may successfully stop the tyrosine kinase inhibitor imatinib. However, questions remain unanswered regarding the biological basis of molecular relapse after imatinib cessation. In IMMUNOSTIM, we monitored 51 patients from the French Stop IMatinib trial for peripheral blood T cells and natural killer cells. Molecular relapse-free survival at 24 months was 45.1% (95% CI: 31.44%–58.75%). At the time of imatinib discontinuation, non-relapsing patients had significantly higher numbers of natural killer cells of the cytotoxic CD56^dim subset than had relapsing patients, while CD56^bright natural killer cells, T cells and their subsets did not differ significantly. Furthermore, the CD56^dim natural killer-cell count was an independent prognostic factor of molecular-relapse free survival in a multivariate analysis. However, expression of natural killer-cell activating receptors, BCR-ABL1⁺ leukemia cell line K562-specific degranulation and cytokine-induced interferon-gamma secretion were decreased in non-relapsing and relapsing patients as compared with healthy individuals. After imatinib cessation, the natural killer-cell count increased significantly and stayed higher in non-relapsing patients than in relapsing patients, while receptor expression and functional properties remained unchanged. Altogether, our results suggest that natural killer cells may play a role in controlling leukemia-initiating cells at the origin of relapse after imatinib cessation, provided that these cells are numerous enough to compensate for their functional defects. Further research will decipher mechanisms underlying functional differences between natural killer cells from patients and healthy individuals and evaluate the potential interest of immunostimulatory approaches in tyrosine kinase inhibitor discontinuation strategies. (ClinicalTrial.gov Identifier NCT00478985)

Variables associated with patient-reported outcomes in persons with chronic myeloid leukemia receiving tyrosine kinase-inhibitor therapy

PURPOSE

Explore patient-reported outcomes (PROs), including health-related quality of life (HRQoL), satisfaction with therapy, impact of the therapy on work and daily life, and concerns related to the therapy and identify variables associated with PROs in persons with chronic myeloid leukemia (CML) receiving tyrosine kinase inhibitors (TKIs).

METHODS

Across-sectional questionnaire was distributed to adults with chronic phase CML and answered anonymously. SF-36 Health Survey was used to measure HRQoL. Our focus was on the physical component summary (PCS) and mental component summary (MCS) components.

RESULTS

Data from 819 respondents receiving TKI-therapy ≥3 months and achieving a complete cytogenetic response were analyzed. Median age was 42 years (range 18-88 years). 652 (80%) were receiving imatinib. Median TKI-therapy duration was 36 months (range 3-178 months). 629 (77%) paid some or all of their TKI costs. In multivariate analyses, female sex, increasing age, lower education level, increasing co-morbidities, concomitant medication, ≥3 symptoms, moderate or severe symptom, switch from imatinib to a second-generation TKI, and higher annual out-of-pocket expense of TKI were significantly associated with lower PCS and/or MCS. However, TKI-therapy duration 3-7 years was significantly associated with better well-being. Higher PCS or MCS score was significantly associated with higher satisfaction level with TKI-therapy and less impact of TKI-therapy on subject's daily life and work. In addition, adverse impact on daily life and work was significantly associated with more interests in TKI-therapy-related issues.

CONCLUSIONS

Social-economic and clinical variables were significantly associated with PROs in persons with CML receiving TKI-therapy.

The value of quality of life assessment in chronic myeloid leukemia patients receiving tyrosine kinase inhibitors

The development of the oral tyrosine kinase inhibitors (TKIs) to treat chronic myeloid leukemia (CML) is one of the great triumphs of cancer research. Although the efficacy of TKIs has dramatically improved the disease-specific overall survival rate, the prevalence of CML is increasing worldwide. Currently, CML patients receive prolonged (even lifelong) treatment, and over the last decade, clinical decision making has become challenging. Therefore, consideration of the effects of TKI therapies on patients' quality of life (QoL) and symptom burden (ie, patient-reported outcomes [PROs]) is now critical to more robustly inform patient care and improve health care quality. Over the last 5 years, a number of studies have generated valuable PRO data, for example, on long-term QoL effects of imatinib therapy or symptom burden of patients switching from imatinib to second-generation TKIs. PRO findings are important, as they provide a unique patient perspective on the burden of the disease and treatments effects. We will review main evidence-based data on the use of PROs in clinical research and highlight the importance of methodological rigor of PRO assessment. Also, we will describe the potential value of using PRO assessment in routine clinical practice, for example, to facilitate timely management of side effects. Areas for future research will also be discussed.

The concept of treatment-free remission in chronic myeloid leukemia

The advent of tyrosine kinase inhibitors (TKI) into the management of patients with chronic myeloid leukemia (CML) has profoundly improved prognosis. Survival of responders is approaching that of the general population but lifelong treatment is still recommended. In several trials, TKI treatment has been stopped successfully in approximately half of the patients with deep molecular response. This has prompted the development of a new concept in the evaluation of CML patients known as 'treatment-free remission'. The future in CML treatment will be to define criteria for the safe and most promising discontinuation of TKI on one hand, and, on the other, to increase the number of patients available for such an attempt. Until safe criteria have been defined, discontinuation of therapy is still experimental and should be restricted to clinical trials or registries. This review will provide an overview of current knowledge as well as an outlook on future challenges.

Imatinib withdrawal syndrome and longer duration of imatinib have a close association with a lower molecular relapse after treatment discontinuation: the KID study

The aim of the Korean Imatinib Discontinuation Study was to identify predictors for safe and successful imatinib discontinuation. A total of 90 patients with a follow-up of ≥12 months were analyzed. After a median follow-up of 26.6 months after imatinib discontinuation, 37 patients lost the major molecular response. The probability of sustained major molecular response at 12 months and 24 months was 62.2% and 58.5%, respectively. All 37 patients who lost major molecular response were retreated with imatinib therapy for a median of 16.9 months, and all achieved major molecular response again at a median of 3.9 months after resuming imatinib therapy. We observed newly developed or worsened musculoskeletal pain and pruritus in 27 (30%) patients after imatinib discontinuation. Imatinib withdrawal syndrome was associated with a higher probability of sustained major molecular response (P=0.003) and showed a trend for a longer time to major molecular response loss (P=0.098). Positivity (defined as ≥ 17 positive chambers) of digital polymerase chain reaction at screening and longer imatinib duration before imatinib discontinuation were associated with a higher probability of sustained major molecular response. Our data demonstrated that the occurrence of imatinib withdrawal syndrome after imatinib discontinuation and longer duration of imatinib were associated with a lower rate of molecular relapse. In addition, minimal residual leukemia measured by digital polymerase chain reaction had a trend for a higher molecular relapse. (Trial registered at ClinicalTrials.gov: NCT01564836).