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Purpose: Haematology patients with high-risk neutropenia are prone to mucosal-barrier injury-associated laboratory-confirmed bloodstream infections (MBI-LCBI). We assessed risk factors for MBI-LCBI including candidaemia in neutropenic haematology patients with fever. Methods: This prospective observational study was performed in six dedicated haematology units in the Netherlands. Eligible haematology patients had neutropenia < 500/mL for ≥ 7 days and had fever. MBI-LCBIs were classified according to Centers for Disease Control (CDC) definitions and were followed until the end of neutropenia > 500/mL or discharge. Results: We included 416 patients from December 2014 until August 2019. We observed 63 MBI-LCBIs. Neither clinical mucositis scores nor the blood level of citrulline at fever onset was associated with MBI-LCBI. In the multivariable analysis, MASCC-score (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.05 to 1.29 per point decrease), intensive chemotherapy (OR 3·81, 95% CI 2.10 to 6.90) and Pichia kudriavzevii (formerly Candida krusei) colonisation (OR 5.40, 95% CI 1.75 to 16.7) were retained as risk factors for MBI-LCBI, while quinolone use seemed protective (OR 0.42, 95% CI 0.20 to 0.92). Citrulline level (OR 1.57, 95% CI 1.07 to 2.31 per µmol/L decrease), active chronic obstructive pulmonary disease (OR 15.4, 95% CI 1.61 to 14.7) and colonisation with fluconazole-resistant Candida (OR 8.54, 95% CI 1.51 to 48.4) were associated with candidaemia. Conclusion: In haematology patients with fever during neutropenia, hypocitrullinaemia at fever onset was associated with candidaemia, but not with bacterial MBI-LCBI. Patients with intensive chemotherapy with a low MASCC-score and colonisation with Pichia kudriavzevii had the highest risk of MBI-LCBI. Trial registration: ClinicalTrials.gov (NCT02149329) at 19-NOV-2014. [ABSTRACT FROM AUTHOR]

Objectives: To describe the real‐world effectiveness and safety of bosutinib in patients with chronic myeloid leukemia (CML). Methods: This was a multi‐center, retrospective, non‐interventional chart review study conducted in 10 hospitals in the United Kingdom and the Netherlands. Results: Eighty‐seven patients were included. Bosutinib was the third‐line tyrosine kinase inhibitor (TKI) in 33 (38%) and fourth‐line in 44 (51%) patients. Median treatment duration was 15.6 months. Among 84 patients in chronic phase (CP) at baseline, 26 (31%) switched to bosutinib due to resistance and 57 (68%) due to intolerance to prior TKIs. Cumulative complete cytogenetic and major molecular response rates in CP patients were 67% and 55%, respectively. After a median follow‐up of 21.5 months, nine (11%) patients in CP died; estimated overall survival rates at 1 and 2 years postbosutinib initiation were 95% and 91%, respectively. Overall, 33/87 (38%) patients discontinued bosutinib due to either lack of efficacy/disease progression (17%), adverse events (14%), death (2%), or other reasons (5%). Eighty‐two (94%) patients experienced ≥1 adverse event possibly related to bosutinib, most commonly diarrhea (52%). Conclusions: Bosutinib used in routine clinical practice in heavily pretreated patients with CML is an effective treatment for patients in CP and is generally tolerable. [ABSTRACT FROM AUTHOR]

Precise and reliable predictive parameters to accurately identify chronic myeloid leukemia (CML) patients who can successfully discontinue their tyrosine kinase inhibitor (TKI) treatment are lacking. One promising parameter is depth of molecular response measured by BCR::ABL1 digital PCR (dPCR). The aim of this study was to validate a previously described prediction cutoff of 0.0023%IS and to assess the value of dPCR for treatment‐free remission (TFR) prediction in relation to other clinical parameters. A droplet‐based dPCR assay assessed BCR::ABL1 %IS prior to TKI discontinuation. The primary endpoint was molecular recurrence (MolR) by 36 months. A total of 186 patients from Canada, Germany, and the Netherlands were included. In patients with a first TKI discontinuation attempt (n = 163), a BCR::ABL1 dPCR < and ≥0.0023%IS had a MolR probability of 33% and 70%, respectively. Patients treated less than 6 years with a BCR::ABL1 dPCR <0.0023%IS had a MolR probability of 31%. After correction for treatment duration, both high dPCR value and the use of imatinib (vs. second‐generation TKI) were significantly associated with a higher risk of MolR (HR of 3.66, 95%CI 2.06–6.51, p <.001; and 2.85, 95%CI 1.25–6.46, p =.013, respectively). BCR::ABL1 dPCR was not associated with TFR outcome after second TKI discontinuation, however, with the limitation of a small number of patients analyzed (n = 23). In conclusion, BCR::ABL1 digital PCR based on the cutoff of 0.0023%IS is a valuable predictive tool to identify CML patients with a high probability of TFR success after first TKI discontinuation, including patients treated for less than 6 years. [ABSTRACT FROM AUTHOR]

Objective: Relapse of AML after allogeneic hematopoietic stem cell transplantation (HSCT) has a poor prognosis, and standard of care therapy is lacking. Early (<6 months) relapse is associated with dismal outcome, while the majority of relapses occur early after transplantation. A more precise indication which patients could benefit from reinduction therapy is warranted. Methods: We retrospectively analyzed outcomes of 83 patients with postallogeneic HSCT relapse. Patients were divided based on intention to treat (curative vs supportive care). Results: Of the 50 patients treated with curative intent, 44% reached complete remission (CR) upon reinduction chemotherapy, and of these patients, 50% survived. Two survivors reached CR after immunotherapy (donor lymphocyte infusion (DLI), without reinduction chemotherapy). Sixty‐nine percent of the survivors had received high‐intensity cytarabine treatment, followed by immunologic consolidation. Relapse <3 months after transplantation was predictive for adverse survival (P = .004), but relapse <6 months was not. In fact, >50% of the survivors had a relapse <6 months. Conclusion: We confirmed the dismal prognosis of postallogeneic HSCT relapse. Importantly, our data demonstrate that patients fit enough to receive high‐dose chemotherapy, even when relapse occurred <6 months, had the best chance to obtain durable remissions, in particular when immunologic consolidation was performed after reaching CR. [ABSTRACT FROM AUTHOR]

Treatment outcome in elderly Acute Myeloid Leukemia (AML) is still very disappointing. Although complete remission rate is around 50-60% the 2 years survival is only in the magnitude of 10-20%. This is mainly due to an overrepresentation of adverse prognostic factors present in elderly AML. As relapses emerge from residual disease present after chemotherapy, intensification of treatment could emerge as a rational strategy. Intensification of chemotherapy by increasing the dose of anthracyclines or addition of gemtuzumab ozogamycin (Mylotarg) to standard chemotherapy indeed has proved to be of advantage in elderly AML. In younger AML autologous peripheral blood stem cell transplantation (AuPBSCT) as post remission treatment in comparison to intensive consolidation chemotherapy has been investigated in a few randomized studies. AuPBSCT showed reduced relapse rates with low non-relapse mortality rates. In elderly AML intensification by AuPBSCT also have been performed although randomized studies are lacking. Nevertheless, in the previous years various reports have suggested the potential utility of AuHSCT in AML of the elderly with encouraging results, albeit mostly in highly selected patients. Acceptable toxicity and a relatively low rate of transplant-related mortality has been notified. However relapses occurred which, irrespective of age, still remains the major cause of treatment failure of AuHSCT in AML. In this review we summarize the experience of AuPBSCT in elderly AML. [ABSTRACT FROM AUTHOR]

Historically, dose selection of anticancer drugs has mainly been based on establishing the maximum tolerated dose in phase 1 clinical trials with a traditional 3 plus 3 design. In the era of targeted therapies and immune-modulating agents, this approach does not necessarily lead to selection of the most favourable dose. This strategy can introduce potentially avoidable toxicity or inconvenience for patients. Multiple changes in drug development could lead to more rational dose selection, such as use of better predictive preclinical models, adaptive and randomised trial design, evaluation of multiple dose levels in late-phase development, assessment of target activity and saturation, and early biomarker use for efficacy and safety evaluation. In this Review, we evaluate the rationale and validation of dose selection in each phase of drug development for anticancer drugs approved by the European Medicines Agency and US Food and Drug Administration from Jan 1, 2020, to June 30, 2023, and give recommendations for dose optimisation to improve safety and patient convenience. In our evaluation, we classified 20 (65%) of the 31 recently registered anticancer agents as potential candidates for dose optimisation, which could be achieved either by reducing the dose (n=10 [32%]) or adjusting the dosage regimen (n=10 [32%]). Dose selection seemed to be adequately justified for nine (29%) of the drugs, whereas the reviewed data were inconclusive for formulating a recommendation on dose optimisation for two (6%) of the drugs. [ABSTRACT FROM AUTHOR]

Simple Summary: Venetoclax has proven to be a promising therapy for newly diagnosed, relapsed and refractory AML patients ineligible for induction chemotherapy. Current ongoing clinical trials are evaluating its effectivity as frontline therapy for all acute myeloid leukemia (AML) patients. However, response rates vary wildly, depending on patient characteristics and mutational profiles. This review elaborates on the efficacy and safety of venetoclax compared to conventional chemotherapy for treatment of AML patients, comparing the response rates, overall survival and adverse events. Moreover, it gives an overview of genetic and epigenetic AML cell characteristics that give enhanced or decreased response to venetoclax and offers insights into the pathogenesis of venetoclax sensitivity and resistance. Additionally, it suggests possible treatment combinations predicted to be successful based on identified mechanisms influencing venetoclax sensitivity of AML cells. Venetoclax is a BCL-2 inhibitor that effectively improves clinical outcomes in newly diagnosed, relapsed and refractory acute myeloid leukemia (AML) patients, with complete response rates (with and without complete blood count recovery) ranging between 34–90% and 21–33%, respectively. Here, we aim to give an overview of the efficacy of venetoclax-based therapy for AML patients, as compared to standard chemotherapy, and on factors and mechanisms involved in venetoclax sensitivity and resistance in AML (stem) cells, with the aim to obtain a perspective of response biomarkers and combination therapies that could enhance the sensitivity of AML cells to venetoclax. The presence of molecular aberrancies can predict responses to venetoclax, with a higher response in NPM1-, IDH1/2-, TET2- and relapsed or refractory RUNX1-mutated AML. Decreased sensitivity to venetoclax was observed in patients harboring FLT3-ITD, TP53, K/NRAS or PTPN11 mutations. Moreover, resistance to venetoclax was observed in AML with a monocytic phenotype and patients pre-treated with hypomethylating agents. Resistance to venetoclax can arise due to mutations in BCL-2 or pro-apoptotic proteins, an increased dependency on MCL-1, and usage of additional/alternative sources for energy metabolism, such as glycolysis and fatty acid metabolism. Clinical studies are testing combination therapies that may circumvent resistance, including venetoclax combined with FLT3- and MCL-1 inhibitors, to enhance venetoclax-induced cell death. Other treatments that can potentially synergize with venetoclax, including MEK1/2 and mitochondrial complex inhibitors, need to be evaluated in a clinical setting. [ABSTRACT FROM AUTHOR]

Introduction: This comprehensive observational study aimed to gain insight into adherence to nilotinib and the effect of (non)adherence on exposure (Cmin) and treatment outcomes. Methods: Chronic myeloid leukemia (CML) patients using nilotinib were followed for 12 months. Adherence was measured by Medication Event Monitoring System (MEMS), pill count, and Medication Adherence Report Scale (MARS-5). Nilotinib Cmin and patient-reported outcomes (i.e., quality of life, side effects, beliefs, satisfaction) were measured at baseline, 3, 6, and 12 months. Results: Sixty-eight patients (57.5 ± 15.0 years, 49% female) participated. Median adherence to nilotinib (MEMS and pill count) was ≥ 99% and adherence < 90% was rare. Self-reported nonadherence (MARS-5) increased in the first year of treatment to a third of patients. In line with the strong beliefs in the necessity of taking nilotinib, forgetting to take a dose was more prevalent than intentionally adjusting/skipping doses. Nilotinib Cmin were generally above the therapeutic target in 95% of patients. Patients reported a variety of side effects, of which fatigue was most frequent. The mean Cmin was higher in patients who reported severe itching and fatigue. The overall 1-year MMR rate ranged from 47 to 71%. Conclusion: Substantial nonadherence (< 90%) to nilotinib was rare and nilotinib Cmin were generally above the therapeutic target. Lack of response in our group of patients was not related to nonadherence or inadequate Cmin. Nevertheless, a considerable number of patients experienced difficulties in adhering to the twice daily fasted dosing regimen, emphasizing the importance of continuous support of medication adherence in CML. Clinical trial registration: NTR3992 (Netherlands Trial Register, www.trialregister.nl) [ABSTRACT FROM AUTHOR]

Objectives: Taking advantage of its food‐dependent bioavailability, the present study investigated the effect of a reduced dose taken with real‐life meals on the pharmacokinetics (PK) of nilotinib in chronic myeloid leukaemia (CML) patients. Methods: Nilotinib was taken fasted (300 mg BID, days 1‐4) or with real‐life meals (200 mg BID, days 5‐11). Rich sampling (days 1, 3, 8, 11) allowed for non‐compartmental PK analysis. Nilotinib exposure (AUC0–12 h ‐Cmin ‐Cmax) and its intra‐ and interpatient variability were compared between the two regimens. Adverse events were recorded by means of a patient diary and ECG monitoring. Results: Fifteen patients aged 40‐74 years participated. Nilotinib PK following 200 mg BID taken with a meal strongly resembled that of 300 mg BID taken fasted (Cmin percentile (P)10‐P90: 665‐1404 ng/mL and 557‐1743 ng/mL, respectively). Meals delayed nilotinib absorption. Intra‐ and interpatient variability were not increased by intake with meals. Nilotinib with food was well tolerated. Conclusion: With support of therapeutic drug monitoring, the use of a reduced 200 mg nilotinib dose with real‐life meals seems feasible and safe. Future (confirmatory) studies should further explore the usefulness of nilotinib dosing together with food, including the relationship with treatment efficacy as well as long‐term effects on quality of life. Clinical Trial Registration: NTR5000 (Netherlands Trial Register, www.trialregister.nl). [ABSTRACT FROM AUTHOR]

Objectives: Acquired missense mutations in the BCR::ABL1 kinase domain (KD) may cause tyrosine kinase inhibitor (TKI) treatment failure. Based on mutation‐specific in vitro derived IC50‐values, alternative TKI may be selected. We assessed clinical practice of BCR::ABL1 KD mutation testing, clinical response in relation to IC50‐values, and clinical outcome of tested patients. Methods: Patients from six Dutch CML reference centers and a national registry were included once a mutational analysis was performed. Reasons for testing were categorized as suboptimal TKI response, and primary or secondary TKI resistance. Results: Four hundred twenty analyses were performed in 275 patients. Sixty‐nine patients harbored at least one mutation. Most analyses were performed because of suboptimal TKI response but with low mutation incidence (4%), while most mutations were found in primary and secondary resistant patients (21% and 51%, respectively). Harboring a BCR::ABL1 mutation was associated with inferior overall survival (HR 3.2 [95% CI, 1.7–6.1; p <.001]). Clinically observed responses to TKI usually corresponded with the predicted TKI sensitivity based on the IC50‐values, but a high IC50‐value did not preclude a good clinical response per se. Conclusions: We recommend BCR::ABL1 KD mutation testing in particular in the context of primary or secondary resistance. IC50‐values can direct the TKI choice for CML patients, but clinical efficacy can be seen despite adverse in vitro resistance. [ABSTRACT FROM AUTHOR]

Chronic myeloid leukemia (CML) is a hematologic neoplasm characterized by the expression of the BCR::ABL1 oncoprotein, a constitutively active tyrosine kinase, resulting in uncontrolled growth and proliferation of cells in the myeloid lineage. Targeted therapy using tyrosine kinase inhibitors (TKIs) such as imatinib, nilotinib, dasatinib, bosutinib, ponatinib and asciminib has drastically improved the life expectancy of CML patients. However, treatment resistance occurs in 10–20% of CML patients, which is a multifactorial problem that is only partially clarified by the presence of TKI inactivating BCR::ABL1 mutations. It may also be a consequence of a reduction in cytosolic TKI concentrations in the target cells due to transporter-mediated cellular distribution. This review focuses on drug-transporting proteins in stem cells and progenitor cells involved in the distribution of TKIs approved for the treatment of CML. Special attention will be given to ATP-binding cassette transporters expressed in lysosomes, which may facilitate the extracytosolic sequestration of these compounds. [ABSTRACT FROM AUTHOR]

Purpose: To obtain insight into the feasibility of, and the patients' perspective on, dried blood spot (DBS) self-sampling by patients with chronic myeloid leukemia (CML) using nilotinib. Methods: Sixty-eight patients with CML using nilotinib participated in this multicenter observational study. Patients were asked to perform blood sampling by means of the DBS method at home just before drug intake (trough level) and to complete a questionnaire including demographics and five questions on their experience with DBS self-sampling. Results: Sixty-one patients (57.5 ± 15.0 years, 49% female) provided 178 DBS samples of which 137 (77%) proved useful in clinical practice. Twenty percent of the samples were rejected because the spot size was too small for analysis. A further 3% were taken at the wrong time. Unsuitable DBS samples were provided by 23 patients. Their educational level was significantly lower than that of patients whose samples were all suitable (p = 0.041). Patients considered DBS self-sampling easy and not painful, and three quarters of the patients performed DBS sampling without additional assistance. Patients' belief in the reliability of DBS self-sampling was moderate to high. It was preferred over venous sampling by 37% of the patients, whereas 39% had no preference. Conclusion: DBS self-sampling by CML patients is feasible in clinical practice provided that patients, particularly those with a lower educational level, are adequately instructed about sample collection with emphasis on timing and volume of sample collection. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: The monitoring of response in chronic myeloid leukemia (CML) is of great importance to identify patients failing their treatment in order to adjust TKI choice and thereby prevent progression to advanced stage disease. Cytogenetic monitoring has a lower sensitivity, is expensive, and requires invasive bone marrow sampling. Nevertheless, chronic myeloid leukemia guidelines continue to recommend performing routine cytogenetic response assessments, even when adequate molecular diagnostics are available. Methods: In a population‐based registry of newly diagnosed CML patients in the Netherlands, all simultaneous cytogenetic and molecular assessments performed at 3, 6, and 12 months were identified and response of these matched assessments was classified according to European Leukemia Net (ELN) recommendations. The impact of discrepant cytogenetic and molecular response classifications and course of patients with additional chromosomal abnormalities were evaluated. Results: The overall agreement of 200 matched assessments was 78%. In case of discordant responses, response at 24 months was consistently better predicted by the molecular outcome. Cytogenetic response assessments provided relevant additional clinical information only in some cases of molecular “warning.” The development of additional cytogenetic abnormalities was always accompanied with molecular failure. Conclusion: We conclude that it is safe to omit routine cytogenetics for response assessment during treatment and to only use molecular monitoring, in order to prevent ambiguous classifications, reduce costs, and reduce the need for invasive bone marrow sampling. Cytogenetic re‐assessment should still be performed when molecular response is suboptimal. [ABSTRACT FROM AUTHOR]

Background Invasive aspergillosis (IA) by a triazole-resistant Aspergillus fumigatus is associated with high mortality. Real-time resistance detection will result in earlier initiation of appropriate therapy. Methods In a prospective study, we evaluated the clinical value of the AsperGenius polymerase chain reaction (PCR) assay in hematology patients from 12 centers. This PCR assay detects the most frequent cyp51A mutations in A. fumigatus conferring azole resistance. Patients were included when a computed tomography scan showed a pulmonary infiltrate and bronchoalveolar fluid (BALf) sampling was performed. The primary end point was antifungal treatment failure in patients with azole-resistant IA. Results Of 323 patients enrolled, complete mycological and radiological information was available for 276 (94%), and probable IA was diagnosed in 99/276 (36%). Sufficient BALf for PCR testing was available for 293/323 (91%). Aspergillus DNA was detected in 116/293 (40%) and A. fumigatus DNA in 89/293 (30%). The resistance PCR was conclusive in 58/89 (65%) and resistance detected in 8/58 (14%). Two had a mixed azole-susceptible/azole-resistant infection. In the 6 remaining patients, treatment failure was observed in 1. Galactomannan positivity was associated with mortality (P =.004) while an isolated positive Aspergillus PCR was not (P =.83). Conclusions Real-time PCR-based resistance testing may help to limit the clinical impact of triazole resistance. In contrast, the clinical impact of an isolated positive Aspergillus PCR on BALf seems limited. The interpretation of the EORTC/MSGERC PCR criterion for BALf may need further specification (eg, minimum cycle threshold value and/or PCR positive on >1 BALf sample). [ABSTRACT FROM AUTHOR]

Summary: Studies on the conditional life expectancy of patients with chronic myeloid leukaemia (CML) are lacking. Using data from the Netherlands Cancer Registry, we examined the life expectancy of patients with CML in the Netherlands diagnosed during 1989–2018. As of the early 2010s, the life expectancy of patients with CML who survived several years after diagnosis came narrowly close to the general population's life expectancy, regardless of age. This finding can essentially be ascribed to the introduction and broader application of tyrosine kinase inhibitors (TKIs) and provide optimism to patients with CML who can look forward to a near‐normal life expectancy in a modern TKI era. [ABSTRACT FROM AUTHOR]

Summary: Most patients with myelodysplastic syndromes (MDS) require therapeutic intervention. However, there are few approved treatments for MDS. To explore reasons, we searched clinicaltrials.gov and clinicaltrialsregister.eu for MDS trials from 2000 to 2020. We assessed which agents were under investigation and analysed clinical trial characteristics and continuation rates from phase I to II to III to approval. As such, we identified 384 unique agents in 426 phase I, 430 phase II and 48 phase III trials. Success rates for phase III trials and agents were low, and MDS trials took markedly longer to complete than the average clinical trial. Although success rates were higher when MDS‐specific phase I trials were conducted, 52% of the agents had not been evaluated in a phase I trial for MDS. MDS trials often failed to include quality of life, an especially important outcome for older MDS patients. Our work identifies factors potentially contributing to the paucity of available agents for MDS. We suggest a framework to improve clinical research in MDS that might ultimately augment the number of available agents. [ABSTRACT FROM AUTHOR]

Objective: To investigate the incidence and severity of adverse drug reactions of cyclosporine using AUC‐targeted therapeutic drug monitoring (TDM) compared to trough level (Ctrough)‐targeted TDM in adult allogeneic stem cell recipients. Methods: Blind, monocenter, intervention study. Subjects were 1:1 randomized into either an AUC group or a Ctrough group. Adverse drug reactions were accessed two and four weeks after start of treatment. Results: Forty patients were included, resulting in 15 evaluable subjects (AUC group) and 13 evaluable subjects (Ctrough group). Grade two/three toxicity was observed in 46% (Ctrough group) versus 60% of subjects (AUC group) (P =.463). There was no significant difference between two and four weeks after start of cyclosporine for nausea (P =.142 resp. P =.122), renal dysfunction (P =.464 resp. P = 1.000), and hypomagnesemia (P = 1.000 resp. P =.411). Subjects in the AUC group reached the therapeutic goal earlier (72,7% versus 43,0% at third sampling point, P =.332) and were within the target range more consistently. Conclusion: This study showed no reduction in incidence and severity of cyclosporine‐induced toxicity with AUC‐ versus trough level‐targeted TDM. Although modeled dosing based on AUC led to faster optimal target attainment, this did not result in less toxicity in the early days after transplantation. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to retrospectively assess C‐lectin‐like molecule 1 (CLL‐1) bimodal expression on CD34+ blasts in acute myeloid leukemia (AML) patients (total N = 306) and explore potential CLL‐1 bimodal associations with leukemia and patient‐specific characteristics. Methods: Flow cytometry assays were performed to assess the deeper immunophenotyping of CLL‐1 bimodality. Cytogenetic analysis was performed to characterize the gene mutation on CLL‐1‐negative subpopulation of CLL‐1 bimodal AML samples. Results: The frequency of a bimodal pattern of CLL‐1 expression of CD34+ blasts ranged from 8% to 65% in the different cohorts. Bimodal CLL‐1 expression was most prevalent in patients with MDS‐related AML (P =.011), ELN adverse risk (P =.002), NPM1 wild type (WT, P =.049), FLT3 WT (P =.035), and relatively low percentages of leukemia‐associated immunophenotypes (P =.006). Additional immunophenotyping analysis revealed the CLL‐1− subpopulation may consist of pre‐B cells, immature myeloblasts, and hematopoietic stem cells. Furthermore, (pre)‐leukemic mutations were detected in both CLL‐1+ and CLL‐1− subfractions of bimodal samples (N = 3). Conclusions: C‐lectin‐like molecule 1 bimodality occurs in about 25% of AML patients and the CLL‐1− cell population still contains malignant cells, hence it may potentially limit the effectiveness of CLL‐1‐targeted therapies and warrant further investigation. [ABSTRACT FROM AUTHOR]

Patients with chronic myeloid leukemia (CML) in deep molecular remission may discontinue tyrosine kinase inhibitor (TKI) treatment without relapse. The present study aims to gain insight into the views of CML patients on TKI treatment discontinuation and identify factors that are associated with their willingness to discontinue treatment. A cross-sectional study, among adult Dutch CML patients was conducted to assess willingness and their views on benefits of and concerns about discontinuation. A total of 185 patients participated of whom 76% were willing to discontinue TKI-treatment. Patients considered the absence of side effects the most important benefit whereas fear of disease recurrence was their most prominent concern. Adequate monitoring was the most important prerequisite for TKI-treatment discontinuation. However, ambiguity with respect to perquisites indicate that patients on long-term TKI treatment should be adequately informed both on the possibility to discontinue treatment and on its benefits, risks, and measures that address risks. [ABSTRACT FROM AUTHOR]

The article offers information on the Chronic myeloid leukemia (CML), a chronic myeloproliferative disease, consistently associated with the presence of the Philadelphia chromosome coding for the BCR-ABL oncoprotein. It mentions the use of tyrosine kinase inhibitors (TKIs) in CML has highly improved prognosis of CML patients; and also mentions adequate provision of information is an important determinant of both medication adherence in CML and successful management of side effects.

Objectives: To obtain insight into patients' reasons for medication (non)adherence in chronic myeloid leukaemia (CML) and needs and wishes regarding information and communication. Methods: A mixed‐method study on the basis of a questionnaire and semi‐structured interviews. The CML patient advocacy group asked patients to participate. Results: Sixty‐one patients (54 ± 12 years, 43% male) using imatinib, dasatinib or nilotinib participated. Fifteen patients (25%) reported to miss an intake at least once a month. Most were not worried about missing an intake and did not discuss missed intakes with their healthcare provider (HCP). Social activities disturbing daily routines and the wish to avoid side effects resulted in nonadherence. Patients wanted extensive and understandable information provided timely on all aspects of CML treatment, in particular on side effects, and a more supportive HCP attitude. Conclusions: Nonadherence to CML medication does not cause concern in all patients and is not discussed pro‐actively. HCP have a clear role in supporting medication adherence in CML and must be aware that social activities disturbing daily routines contribute to nonadherence. HCP should discuss (non)adherence in a direct manner, motivate patients to play an active role in managing their medication and timely provide extensive and understandable information on all aspects of CML. [ABSTRACT FROM AUTHOR]

Background: Tyrosine kinase inhibitors (TKIs) have improved the survival of patients with chronic myeloid leukaemia. Many patients have deep molecular responses, a prerequisite for TKI therapy discontinuation. We aimed to define precise conditions for stopping treatment.Methods: In this prospective, non-randomised trial, we enrolled patients with chronic myeloid leukaemia at 61 European centres in 11 countries. Eligible patients had chronic-phase chronic myeloid leukaemia, had received any TKI for at least 3 years (without treatment failure according to European LeukemiaNet [ELN] recommendations), and had a confirmed deep molecular response for at least 1 year. The primary endpoint was molecular relapse-free survival, defined by loss of major molecular response (MMR; >0·1% BCR-ABL1 on the International Scale) and assessed in all patients with at least one molecular result. Secondary endpoints were a prognostic analysis of factors affecting maintenance of MMR at 6 months in learning and validation samples and the cost impact of stopping TKI therapy. We considered loss of haematological response, progress to accelerated-phase chronic myeloid leukaemia, or blast crisis as serious adverse events. This study presents the results of the prespecified interim analysis, which was done after the 6-month molecular relapse-free survival status was known for 200 patients. The study is ongoing and is registered with ClinicalTrials.gov, number NCT01596114.Findings: Between May 30, 2012, and Dec 3, 2014, we assessed 868 patients with chronic myeloid leukaemia for eligibility, of whom 758 were enrolled. Median follow-up of the 755 patients evaluable for molecular response was 27 months (IQR 21-34). Molecular relapse-free survival for these patients was 61% (95% CI 57-64) at 6 months and 50% (46-54) at 24 months. Of these 755 patients, 371 (49%) lost MMR after TKI discontinuation, four (1%) died while in MMR for reasons unrelated to chronic myeloid leukaemia (myocardial infarction, lung cancer, renal cancer, and heart failure), and 13 (2%) restarted TKI therapy while in MMR. A further six (1%) patients died in chronic-phase chronic myeloid leukaemia after loss of MMR and re-initiation of TKI therapy for reasons unrelated to chronic myeloid leukaemia, and two (<1%) patients lost MMR despite restarting TKI therapy. In the prognostic analysis in 405 patients who received imatinib as first-line treatment (learning sample), longer treatment duration (odds ratio [OR] per year 1·14 [95% CI 1·05-1·23]; p=0·0010) and longer deep molecular response durations (1·13 [1·04-1·23]; p=0·0032) were associated with increasing probability of MMR maintenance at 6 months. The OR for deep molecular response duration was replicated in the validation sample consisting of 171 patients treated with any TKI as first-line treatment, although the association was not significant (1·13 [0·98-1·29]; p=0·08). TKI discontinuation was associated with substantial cost savings (an estimated €22 million). No serious adverse events were reported.Interpretation: Patients with chronic myeloid leukaemia who have achieved deep molecular responses have good molecular relapse-free survival. Such patients should be considered for TKI discontinuation, particularly those who have been in deep molecular response for a long time. Stopping treatment could spare patients from treatment-induced side-effects and reduce health expenditure.Funding: ELN Foundation and France National Cancer Institute. [ABSTRACT FROM AUTHOR]

Controversy exists whether internal tandem duplication of FMS-like tyrosine kinase 3 (FLT3-internal tandem duplication [ITD]) allelic ratio (AR) and/or length of the ITD should be taken into account for risk stratification of pediatric acute myeloid leukemia (AML) and whether it should be measured on RNA or DNA. Moreover, the ITD status may be of relevance for selecting patients eligible for FLT3 inhibitors. Here, we included 172 pediatric AML patients, of whom 36 (21%) harbored FLT3-ITD as determined on both RNA and DNA. Although there was a good correlation between both parameters ARspearman = 0.62 (95% confidence interval, 0.22-0.87) and ITDlengthspearman = 0.98 (95% confidence interval, 0.90-1.00), only AR ≥ 0.5 and length ≥48 base pairs (bps) based on RNA measurements were significantly associated with overall survival (AR: Plogrank = .008; ITDlength: Plogrank = .011). In large ITDs (>156 bp on DNA) a remarkable 90-bp difference exists between DNA and RNA, including intron 14, which is spliced out in RNA. Ex vivo exposure (n = 30) to FLT3 inhibitors, in particular to the FLT3-specific inhibitor gilteritinib, showed that colony-forming capacity was significantly more reduced in FLT3-ITD-AR ≥ 0.5 compared with ITD-AR-low and ITD- patient samples (P < .001). RNA-based FLT3-ITD measurements are recommended for risk stratification, and the relevance of AR regarding eligibility for FLT3-targeted therapy warrants further study. [ABSTRACT FROM AUTHOR]

Adequate information on oral anticancer agent (OACA) use is an essential element of optimal cancer care. The present study aimed to get insight into the experiences of patients with information on OACA treatment and their characteristics regarding information dissatisfaction. Patients of four Dutch university hospitals using OACA participated in this observational study and completed the Satisfaction with Information about Medicines Scale (SIMS), EORTC Quality of Life Questionnaire-C30, Brief Illness Perception Questionnaire, and Beliefs about Medicines Questionnaire-Specific. Logistic regression analyses were used to determine factors associated with dissatisfaction with information. Patients (n = 208) using capecitabine (35%), lenalidomide (15%), imatinib (14%), temozolomide (12%), sunitinib (11%), thalidomide (5%), dasatinib (4%), erlotinib (2%), and nilotinib (2%) participated. Information on the following SIMS-items was inadequate: how OACA elicit their effect, how long it takes before treatment works, how to conclude that treatment is effective, the risk of side effects and its management, interference with sex life, drowsiness, interference with other medication and alcohol and what to do in case of a missed dose. Younger age, hematological malignancy, dyspnoea, positive perception of consequences of the cancer, low perception of treatment control, and indifferent attitude towards OACA were associated with dissatisfaction with information. In conclusion, a considerable number of patients would have appreciated receiving more information on specific issues relating to the consequences of OACA treatment such as the effects and side effects of OACA and the interference of treatment with various aspects of their daily life. Oncologists, hematologists, lung-oncologists and pharmacists may reconsider the provision of information on OACA treatment. [ABSTRACT FROM AUTHOR]

Background: The antitumor drug nilotinib has a large inter- and intra individual variability in pharmacokinetics. Adherence to treatment may substantially influence plasma levels and has been recognized as the most important determinant of treatment failure in chronic myeloid leukemia (CML). A better understanding of the various factors contributing to the efficacy of treatment is essential for the development of interventions to optimize the treatment of chronic phase CML (CP-CML) with a protein kinase inhibitor like nilotinib. Methods/Design: In this multicenter prospective observational cohort study 70 adult patients with CP-CML starting treatment with nilotinib will be followed up for at least 12 months. Response to treatment is evaluated after 3, 6 and 12 months. Adherence is primarily assessed by counting the daily intake of nilotinib capsules by means of a medication event monitoring system (MEMS). Before the start of nilotinib treatment and after 3, 6 and 12 months, patients are asked to fill in a comprehensive questionnaire including topics on quality of life, side effects, attitude towards disease and medication, the patients' appreciation of information received about the medication, and discontinuation, and trough plasma levels of nilotinib are measured. Discussion: The present study aims to get more insight into the efficacy of treatment with nilotinib and the various aspects that govern optimal response, of which adherence is a primary endpoint. We hypothesize that patients who experience inadequate response levels to nilotinib are less adherent. In addition, their plasma levels of nilotinib may be lower. We expect that our findings will be useful for health care professionals to support patients with the use of nilotinib in order to derive optimal benefit from their medication. [ABSTRACT FROM AUTHOR]

Background: The antitumor drug nilotinib has a large inter- and intra individual variability in pharmacokinetics. Adherence to treatment may substantially influence plasma levels and has been recognized as the most important determinant of treatment failure in chronic myeloid leukemia (CML). A better understanding of the various factors contributing to the efficacy of treatment is essential for the development of interventions to optimize the treatment of chronic phase CML (CP-CML) with a protein kinase inhibitor like nilotinib. Methods/design: In this multicenter prospective observational cohort study 70 adult patients with CP-CML starting treatment with nilotinib will be followed up for at least 12 months. Response to treatment is evaluated after 3, 6 and 12 months. Adherence is primarily assessed by counting the daily intake of nilotinib capsules by means of a medication event monitoring system (MEMS). Before the start of nilotinib treatment and after 3, 6 and 12 months, patients are asked to fill in a comprehensive questionnaire including topics on quality of life, side effects, attitude towards disease and medication, the patients' appreciation of information received about the medication, and discontinuation, and trough plasma levels of nilotinib are measured. Discussion: The present study aims to get more insight into the efficacy of treatment with nilotinib and the various aspects that govern optimal response, of which adherence is a primary endpoint. We hypothesize that patients who experience inadequate response levels to nilotinib are less adherent. In addition, their plasma levels of nilotinib may be lower. We expect that our findings will be useful for health care professionals to support patients with the use of nilotinib in order to derive optimal benefit from their medication. [ABSTRACT FROM AUTHOR]

Reduced-intensity conditioning ( RIC)-allo SCT is increasingly used for acute myelogenous leukemia. Limited data are available for the comparison of peripheral blood stem cells with bone marrow for RIC-allo SCT. We used the European Group for Blood and Marrow Transplantation ( EBMT) ALWP data to compare the outcome of mobilized peripheral blood stem cells ( PBSC) ( n = 1430) vs. bone marrow ( BM) ( n = 107) for acute myelogenous leukemia ( AML) patients with complete remission that underwent RIC-allo SCT from compatible sibling donors. The leukemia features, the disease status, and the time from diagnosis were similar between the two groups. Engraftment was achieved in 99% and 93% in the PBSC and BM groups, respectively ( P < 0.0001). The day of engraftment was significantly earlier for the PBSC vs. the BM group, 15 (1-59) and 19 (5-69), respectively ( P < 0.001). Acute GVHD, severe GVHD (grade III-IV) and chronic GVHD did not differ between the groups. leukemia-free survival ( LFS), relapse, and non-relapsed mortality ( NRM) were 51 ± 2%, 32 ± 1%, and 17 ± 1% vs. 50 ± 6%, 38 ± 6%, and 12 ± 3% for the PBSC and BM groups, respectively. Our results indicate faster engraftment, but no difference in GVHD, LFS, relapse, and NRM when comparing PBSC to BM grafts from sibling donors following RIC conditioning. This is the first study comparing PBSC to BM grafts in the RIC setting, analyzing a homogeneous population of patients with AML in remission. Whether PBSC should be preferred for advanced phases of the disease, where the outcome is dominated by relapse incidences, needs further investigation. [ABSTRACT FROM AUTHOR]

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • The population pharmacokinetics and limited sampling strategies for ciclosporin monitoring have been extensively studied in renal and liver transplant recipients. Little is known about the pharmacokinetics of ciclosporin in patients undergoing haematopoietic allogeneic stem cell transplantation (HSCT). • It is anticipated that there is a difference in pharmacokinetics in patients after kidney or liver transplantation compared with patients undergoing stem cell transplantation, because of mucositis and interacting drugs (e.g. fluconazole). • Data on the pharmacokinetics of ciclosporin and the relationship between its systemic exposure, as reflected by the area under the curve (AUC), and the biological effect as graft vs. host-disease (GVHD) prophylaxis and graft vs. tumour (GVT) response are scarce in patients after HSCT. WHAT THIS STUDY ADDS • A pharmacokinetic model was developed for orally and intravenously administered ciclosporin, enabling an adequate estimate of the systemic exposure of ciclosporin in patients after HSCT. A limited sampling strategy was tested that may serve as a tool to study the optimum systemic exposure (AUC) of ciclosporin in HSCT to prevent GVHD but establish adequate GVT response and to guide therapeutic drug monitoring. AIM To develop a population pharmacokinetic model of ciclosporin (CsA) in haematopoietic allogeneic stem cell transplantation to facilitate a limited sampling strategy to determine systemic exposure (area under the curve [AUC]), in order to optimize CsA therapy in this patient population. METHODS The pharmacokinetics of CsA were investigated prospectively in 20 patients following allogeneic haematopoietic stem cell transplantation (HSCT). CsA was given twice daily, as a 3 h i.v. infusion starting at day 1 of the conditioning scheme, and orally later on, when oral intake was well tolerated. Fluconazole was given as antimycotic prophylaxis. Pharmacokinetic parameter estimation was performed using nonlinear mixed effect modelling as implemented in the NONMEM program. A first order absorption model with lag time was compared with Erlang frequency distribution and Weibull distribution models. The influence of demographic variables on the individual empirical Bayesian estimates of clearance and distribution volume was tested. Subsequently two limited sampling strategies (LSS) were evaluated: posterior Bayesian fitting and limited sampling equations. RESULTS Twenty patients were included and 435 samples were collected after i.v. and oral administration of CsA. A two compartment model with first order absorption best described the data. Clearance (CL) was 21.9 l h−1 (relative standard deviation [RSD]± 5.2%) with an inter-individual variability of 21%. The central volume of distribution ( Vc) was 18.3 l (RSD ± 8.7%) with an inter-individual variability of 29%. Bioavailability ( F) was 0.71 (RSD ± 9.9%) with and inter-individual variability of 25% and lag time ( tlag) was 0.44 h (RSD 5.5%). Weight, body surface area, haematocrit, albumin, ALAT and ASAT had no significant influence on pharmacokinetic parameters. The best multiple point combination for posterior Bayesian fitting, in terms of estimating systemic CsA exposure, appeared to be C0 + C2 + C3. Two selected LSS two time point equations and all selected three and four time point equations predicted de all AUC(0,12 h) within 15% bias and prediction. CONCLUSIONS The i.v. and oralcurves were best described with a two compartment model with first-order absorption with lag time. With the Bayesian estimators from this model, the area under the concentration−time curve in HSCT patients taking fluconazole can be estimated with only three blood samples (0, 2, 3 h) with a bias of 1% and precision of 4%. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the cost-effectiveness of posaconazole versus fluconazole for the prevention of invasive fungal infections (IFI) in graft-versus-host disease (GVHD) patients in the Netherlands. A decision analytic model was developed based on a double-blind randomized trial that compared posaconazole with fluconazole antifungal prophylaxis in recipients of allogeneic HSCT with GVHD who were receiving immunosuppressive therapy (Ullmann et al., N Engl J Med 356:335-347, 2007). Clinical events were modeled with chance nodes reflecting probabilities of IFIs, IFI-related death, and death from other causes. Data on life expectancy, quality-of-life, medical resource consumption, and costs were obtained from the literature. The total cost with posaconazole amounted to 9,428 (95% uncertainty interval 7,743-11,388), which is 4,566 (2,460-6,854) more than those with fluconazole. Posaconazole prophylaxis resulted in 0.17 (0.02-0.36) quality adjusted life year (QALY) gained compared to fluconazole prophylaxis, corresponding to an incremental cost effectiveness ratio (ICER) of 26,225 per QALY gained. A scenario analysis demonstrated that at an increased background IFI risk (from 9% to 15%) the ICER was 13,462 per QALY. Given the underlying data and assumptions, posaconazole prophylaxis is expected to be cost-effective relative to fluconazole in recipients of allogeneic HSCT developing GVHD in the Netherlands. The cost-effectiveness of posaconazole depends on the IFI risk, which can vary by hospital. [ABSTRACT FROM AUTHOR]

Background: Acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) patients experience prolonged neutropenia after treatment with intensive chemotherapy, leading to a high risk of invasive fungal infections (IFI). The present study evaluates the cost effectiveness of posaconazole vs. standard azoles for the prevention of IFIs in neutropenic patients in the Netherlands. Methods: A decision-tree model was developed using data from a randomized trial that compared posaconazole and standard azole (fluconazole or itraconazole) prophylaxis in neutropenic patients receiving remission–induction chemotherapy for AML/MDS (Cornely et al., N Engl J Med 2007; 356:348–359). Following initiation of prophylaxis, clinical events are modeled with chance nodes reflecting probabilities of IFIs, IFI-related death, and death from other causes. Patients surviving the prophylaxis are assumed to have a life expectancy according to the underlying condition. This allows translation of the trial outcomes to a lifetime horizon. Data on life expectancy, quality of life, medical resource consumption and costs were obtained from the literature. Model outcomes include cost per life year (LY) gained and cost per quality adjusted life year (QALY) gained. Results: The total cost (treatment of breakthrough IFI + prophylaxis) for posaconazole amounted to €4412 (95% uncertainty interval €3403–€5666), which is −€183 (−€1985 to €1564) less than costs with standard azoles. Posaconazole prophylaxis resulted in 0.08 (0.02–0.15) QALYs gained in comparison with prophylaxis with standard azoles. Results from a probabilistic sensitivity analysis indicate that there is a 90% probability that the cost per QALY gained with posaconazole is below €20 000. Additional scenario analyzes with different assumptions confirmed these findings. Conclusion: Given the underlying data and assumptions, the economic evaluation demonstrated that posaconazole prophylaxis is expected to be cost-effective compared with fluconazole/itraconazole in neutropenic AML/MDS patients after intensive chemotherapy. [ABSTRACT FROM AUTHOR]

The Hermansky–Pudlak syndrome (HPS) is a rare genetically heterogeneous autosomal recessive disorder, characterized by tyrosinase-positive oculocutaneous albinism, platelet dysfunction and lysosomal ceroid lipofuscin storage. This is caused by defects in lysosome-related organelles. In humans eight different types of the syndrome are known, of which a short overview is given. The clinical features and a novel mutation of a patient with HPS type 5 are described here. [ABSTRACT FROM AUTHOR]

Simple Summary: In hematological malignancies, genome-wide sequencing studies found the process of splicing to be surprisingly frequently disrupted. While recent studies characterized altered splicing in relation to splicing factor mutations in AML, this study explored differential splicing profiles associated with two most common aberrations in AML: FLT3-ITD and NPM1 mutations. We identified the differential splicing of FAB-type specific gene sets in FLT3-ITD+/NPM1+ specimens as compared to FLT3-ITD−/NPM1− samples. The primary functions perturbed by differential splicing in all three FAB types included cell cycle control and DNA damage response. Interestingly, differential expression mainly affected genes involved in hematopoietic differentiation. Our findings increase our understanding of how genetic mutations translate to phenotypic features of AML cells to further improve response predictions and to find innovative therapeutic approaches. Altogether, to the best of our knowledge, this is the first study to report differential splicing profiles associated with FLT3-ITD with a concomitant NPM1 mutation in AML. Despite substantial progress achieved in unraveling the genetics of AML in the past decade, its treatment outcome has not substantially improved. Therefore, it is important to better understand how genetic mutations translate to phenotypic features of AML cells to further improve response predictions and to find innovative therapeutic approaches. In this respect, aberrant splicing is a crucial contributor to the pathogenesis of hematological malignancies. Thus far, altered splicing is well characterized in relation to splicing factor mutations in AML. However, splicing profiles associated with mutations in other genes remain largely unexplored. In this study, we explored differential splicing profiles associated with two of the most common aberrations in AML: FLT3-ITD and NPM1 mutations. Using RNA-sequencing data of a total of 382 primary AML samples, we found that the co-occurrence of FLT3-ITD and mutated NPM1 is associated with differential splicing of FAB-type specific gene sets. Despite the FAB-type specificity of particular gene sets, the primary functions perturbed by differential splicing in all three FAB types include cell cycle control and DNA damage response. Interestingly, we observed functional divergence between alternatively spliced and differentially expressed genes in FLT3-ITD+/NPM1+ samples in all analyzed FAB types, with differential expression affecting genes involved in hematopoietic differentiation. Altogether, these observations indicate that concomitant FLT3-ITD and mutated NPM1 are associated with the maturation state-specific differential splicing of genes with potential oncogenic relevance. [ABSTRACT FROM AUTHOR]

Background: Medication non-adherence is associated with poor health outcomes and increased health care costs. Depending on definitions, reported non-adherence rates in cancer patients ranges between 16 and 100%, which illustrates a serious problem. In malignancy, non-adherence reduces chances of achievement of treatment response and may thereby lead to progression or even relapse. Except for Chronic Myeloid Leukemia (CML), the extent of non-adherence has not been investigated in hematological-oncological patients in an outpatient setting. In order to explore ways to optimize cancer treatment results, this study aimed to assess the prevalence of self-administered medication non-adherence and to identify potential associated factors in hematological-oncological patients in their home situation.Methods: This is an exploratory cross-sectional study, carried out at the outpatient clinic of the Department of Hematology at the VU University medical center, Amsterdam, the Netherlands between February and April 2014. Hematological-oncological outpatients were sent questionnaires retrieving information on patient characteristics, medication adherence, beliefs about medication, anxiety, depression, coping, and quality of life. We performed uni- and multivariable analysis to identify predictors for medication non-adherence.Results: In total, 472 participants were approached of which 259 (55%) completed the questionnaire and met eligibility criteria. Prevalence of adherence in this group (140 male; 54,1%; median age 60 (18-91)) was 50%. In univariate analysis, (lower) age, (higher) education level, living alone, working, perception of receiving insufficient social support, use of bisphosphonates, depression, helplessness (ICQ), global health, role function, emotional function, cognitive function, social functioning, fatigue, dyspnea, diarrhea were found to be significantly related (p = <0.20) to medication non-adherence. In multivariable analysis, younger age, (higher) education level and fatigue remained significantly related (p = <0.10) to medication non-adherence.Conclusions: This cross-sectional study shows that 50% of the participants were non-adherent. Lower age, living alone and perception of insufficient social support were associated factors of non-adherence in hematological-oncological adult patients in their home-situation. [ABSTRACT FROM AUTHOR]

Background: The antitumor drug nilotinib has a large inter- and intra individual variability in pharmacokinetics. Adherence to treatment may substantially influence plasma levels and has been recognized as the most important determinant of treatment failure in chronic myeloid leukemia (CML). A better understanding of the various factors contributing to the efficacy of treatment is essential for the development of interventions to optimize the treatment of chronic phase CML (CP-CML) with a protein kinase inhibitor like nilotinib.Methods/design: In this multicenter prospective observational cohort study 70 adult patients with CP-CML starting treatment with nilotinib will be followed up for at least 12 months. Response to treatment is evaluated after 3, 6 and 12 months. Adherence is primarily assessed by counting the daily intake of nilotinib capsules by means of a medication event monitoring system (MEMS). Before the start of nilotinib treatment and after 3, 6 and 12 months, patients are asked to fill in a comprehensive questionnaire including topics on quality of life, side effects, attitude towards disease and medication, the patients' appreciation of information received about the medication, and discontinuation, and trough plasma levels of nilotinib are measured.Discussion: The present study aims to get more insight into the efficacy of treatment with nilotinib and the various aspects that govern optimal response, of which adherence is a primary endpoint. We hypothesize that patients who experience inadequate response levels to nilotinib are less adherent. In addition, their plasma levels of nilotinib may be lower. We expect that our findings will be useful for health care professionals to support patients with the use of nilotinib in order to derive optimal benefit from their medication.Trial Registration: Netherlands Trial Registry NTR3992. [ABSTRACT FROM AUTHOR]