Effects of age on prognosis with imatinib mesylate therapy for patients with Philadelphia chromosome-positive chronic myelogenous leukemia

Impact of age and comorbidities on the efficacy and tolerability of bosutinib in previously treated patients with chronic myeloid leukemia: results from the phase 4 BYOND study

In the phase 4 BYOND trial, patients with pretreated chronic myeloid leukemia (CML) received bosutinib (starting dose: 500 mg/day). Efficacy and safety after ≥3 years of follow-up in 156 patients with Philadelphia chromosome-positive chronic phase CML by age and Charlson Comorbidity Index scores (without the age component; mCCI) is reported. Cumulative major molecular response rates at any time on treatment were 73.6%, 64.5%, and 74.1% in patients <65, 65-74, and ≥75 years of age, and 77.9%, 63.0%, and 59.3% in patients with mCCI scores 2, 3, and ≥4, respectively. Patients <65, 65-74, and ≥75 years of age experienced grade 3/4 treatment-emergent adverse events (TEAEs) at rates of 74.7%, 78.8%, and 96.4% and permanent discontinuations due to AEs at rates of 22.1%, 39.4%, and 46.4%, respectively. In patients with mCCI 2, 3, and ≥4, respective rates of grade 3/4 TEAEs were 77.8%, 77.8%, and 86.7%, and permanent discontinuations due to AEs were 25.3%, 33.3%, and 43.3%. In conclusion, a substantial proportion of patients maintained/achieved cytogenetic and molecular responses across age groups and mCCI scores. Older patients (≥75 years) and those with high comorbidity burden (mCCI ≥4) may require more careful monitoring due to the increased risk of TEAEs. Clinicaltrials.gov: NCT02228382.

Prognosis in Chronic Myeloid Leukemia: Baseline Factors, Dynamic Risk Assessment and Novel Insights

The introduction of tyrosine kinase inhibitors (TKIs) has changed the treatment paradigm of chronic myeloid leukemia (CML), leading to a dramatic improvement of the outcome of CML patients, who now have a nearly normal life expectancy and, in some selected cases, the possibility of aiming for the more ambitious goal of treatment-free remission (TFR). However, the minority of patients who fail treatment and progress from chronic phase (CP) to accelerated phase (AP) and blast phase (BP) still have a relatively poor prognosis. The identification of predictive elements enabling a prompt recognition of patients at higher risk of progression still remains among the priorities in the field of CML management. Currently, the baseline risk is assessed using simple clinical and hematologic parameters, other than evaluating the presence of additional chromosomal abnormalities (ACAs), especially those at "high-risk". Beyond the onset, a re-evaluation of the risk status is mandatory, monitoring the response to TKI treatment. Moreover, novel critical insights are emerging into the role of genomic factors, present at diagnosis or evolving on therapy. This review presents the current knowledge regarding prognostic factors in CML and their potential role for an improved risk classification and a subsequent enhancement of therapeutic decisions and disease management.

Efficacy and safety of nilotinib as frontline treatment in elderly (> 65 years) chronic myeloid leukemia patients outside clinical trials

Here, we report real-world evidence on the safety and efficacy of nilotinib as a first-line treatment in elderly patients with chronic phase CML, treated in 18 Italian centers. Sixty patients aged > 65 years (median age 72 years (65-84)) were reported: 13 patients were older than 75 years. Comorbidities were recorded at baseline in 56/60 patients. At 3 months of treatment, all patients obtained complete hematological response (CHR), 43 (71.6%) an early molecular response (EMR), while 47 (78%) reached a complete cytogenetic response (CCyR). At last follow-up, 63.4% of patients still had a deep molecular response (MR4 or better), 21.6% reached MR3 as best response and 11.6% persisted without MR. Most patients (85%) started the treatment at the standard dose (300 mg BID), maintained at 3 months in 80% of patients and at 6 months in 89% of them. At the last median follow-up of 46.3 months, 15 patients discontinued definitively the treatment (8 due to side effects, 4 died for unrelated CML causes, 1 for failure, 2 were lost to follow-up). One patient entered in treatment-free remission. As to safety, 6 patients (10%) experienced cardiovascular events after a median time of 20.9 months from the start. Our data showed that nilotinib could be, as first-line treatment, effective and relatively safe even in elderly CML patients. In this setting, more data in the long term are needed about possible dose reduction to improve the tolerability, while maintaining the optimal molecular response.

Long term follow-up of frontline Dasatinib in older patients with chronic myeloid leukemia in chronic phase treated outside clinical trials: a real-life cohort observational study

BACKGROUND

A limited amount of data has been published in chronic-phase chronic myeloid leukemia (CP-CML) patients aged >75 years treated frontline with second-generation tyrosine kinase inhibitors.

AIMS

To address this issue in a clinical 'real-life' setting, we retrospectively analyzed 45 CP-CML patients (pts) followed in 20 Italian Centers and treated frontline with dasatinib (DAS).

PATIENTS AND METHODS

Median age was 78.4 years (range 75-89.2 years). DAS starting dose was 100 mg QD in 35 pts (77.7%), 80 mg QD in 1 pts (2.2%) and 50 mg QD in 9 pts (20.1%), respectively. The median follow-up was 42.6 months (IQR 20.4 - 63.3).

RESULTS

Grade 3 and 4 side effects, both hematological and non-hematological, were detected in 6 (13.3%) and 12 (26.6%) pts, respectively. Pleural effusions of all grades occurred in 13 pts (28.8%) after a median period of DAS exposure of 14.7 months (IQR 3.0 - 33.1). The rates of DAS dose reduction and permanent drug discontinuation were 53.3% and 20.0%, respectively. As the best response, 42/45 patients (93.3%) achieved a complete cytogenetic response (CCyR), 35/45 (77.7%) a major molecular response (MMR) and 24/45 (53.3%) a deep molecular response (both MR 4.0 and MR 4.5). Only 1 patient (2.2%) progressed to the blast phase after 13 months of therapy; 8 deaths were observed (1 CML-related and 7 CML-unrelated). Cumulative event-free survival and overall survival at 36 months were 64.7% (95%, CI 49.4 - 80.0) and 82.3% (95%, CI 70.3-94.3), respectively.

CONCLUSION

These findings, although evaluated in a limited and selected cohort of patients, suggest that DAS might be effective in older patients (aged >75 years) affected by CP-CML with acceptable toxicity.

Prognostic Factors for Overall Survival In Chronic Myeloid Leukemia Patients: A Multicentric Cohort Study by the Italian CML GIMEMA Network

An observational prospective study was conducted by the CML Italian network to analyze the role of baseline patient characteristics and first line treatments on overall survival and CML-related mortality in 1206 newly diagnosed CML patients, 608 treated with imatinib (IMA) and 598 with 2^nd generation tyrosine kinase inhibitors (2GTKI). IMA-treated patients were much older (median age 69 years, IQR 58-77) than the 2GTKI group (52, IQR 41-63) and had more comorbidities. Estimated 4-year overall survival of the entire cohort was 89% (95%CI 85.9-91.4). Overall, 73 patients (6.1%) died: 17 (2.8%) in the 2GTKI vs 56 (9.2%) in the IMA cohort (adjusted HR=0.50; 95% CI=0.26-0.94), but no differences were detected for CML-related mortality (10 (1.7%) vs 11 (1.8%) in the 2GTKIs vs IMA cohort (sHR=1.61; 0.52-4.96). The ELTS score was associated to CML mortality (high risk vs low, HR=9.67; 95%CI 2.94-31.74; p<0.001), while age (per year, HR=1.03; 95%CI 1.00-1.06; p=0.064), CCI (4-5 vs 2, HR=5.22; 95%CI 2.56-10.65; p<0.001), ELTS score (high risk vs low, HR=3.11; 95%CI 1.52-6.35, p=0.002) and 2GTKI vs IMA (HR=0.26; 95%CI 0.10-0.65, p=0.004) were associated to an increased risk of non-related CML mortality. The ELTS score showed a better discriminant ability than the Sokal score in all comparisons.

Measuring prognosis in chronic myeloid leukemia: what's new?

Introduction: The outcome of chronic myeloid leukemia (CML) patients in chronic phase has changed after the introduction of tyrosine kinase inhibitors (TKIs). The life expectancy is actually similar to that of the general population. Prognostic stratification at baseline is part of a patient-centered approach to decide the best therapeutic approach.Areas covered: In this review, the current prognostic factors examined at baseline are detailed and the meaning is explained. A broad research on Medline, Embase and archives from EHA and ASH congresses, was performed. Prognostic factors have been divided into patient-related (age, gender, comorbidities, etc.) and disease-related (additional cytogenetic abnormalities, type of transcript, etc). New information about genomic data and the potential role of patient-reported outcomes is also discussed.Expert Opinion: Prognostic factors at baseline should be considered to evaluate the long-term probability of disease-related death, the possible toxicity, and the projected long-term overall survival. The genomic assessment would provide the basis for a genomic-based risk and help in oriented decision-making process.

The multi-tyrosine kinase inhibitor ponatinib for chronic myeloid leukemia: Real-world data

Development of the highly selective targeted tyrosine kinase inhibitors (TKIs) has expanded the therapeutic options for chronic myeloid leukemia (CML). Patients undergoing TKI therapy should be closely monitored to ensure that the best therapeutic response and quality of life are achieved, and to control suboptimal responses and adverse events. Despite the high rate of response using current first-line TKIs, treatment failure may still occur, and resistance is considered a challenge in the treatment of patients with CML. The third-generation TKI, ponatinib, is a potent orally bioavailable pan BCR-ABL inhibitor that inhibits both wild-type and mutant BCR-ABL1 kinase, including the "gatekeeper" T315I mutation, which is resistant to all other currently available TKIs. This paper reviews the effectiveness, feasibility, and safety of ponatinib in the real-life clinical management of CML. Potential prognostic factors in identifying patients most likely to benefit from ponatinib treatment will be discussed, and case presentations illustrating situations encountered in real-life clinical practice are described. Ponatinib is effective in patients who have received prior TKIs in clinical studies as well as under real-life conditions. Nevertheless, the risk/benefit balance must be evaluated for each patient, particularly considering disease state, mutational status, treatment line, intolerance/resistance to prior TKIs, age, frailty, and specific comorbidities.

CML in Elderly: Does Age Matter?

The median age of diagnosis for chronic myeloid leukemia (CML) in India is 35 years on the contrary to western literature which is 47 years. The outcome of the elderly patient in CML TKI era is not reported from the Indian population. However, Western literature suggests that use of TKI alleviate the adverse impact of age in outcomes of CML. This study was carried out to analyze the clinical profile and outcome of elderly, in comparison with younger patients with CML. We retrospectively analyzed CML patients treated at our department from January 2008 to December 2017. The data cutoff date was December 2018. The cohorts of 712 patients were divided into two groups. Patients belonging to the age group of ≥ 60 years were classified as the study group and those who were 18-60 years were used as controls. Patient's clinical history, examination and milestones in terms of achieving hematological, molecular responses and toxicity profile were also recorded. The total of 712 patients, 52 patients in the study group and 660 patients in the control group were treated during the study period. The study group was having more co-morbidities than the control group (15.3% vs. 4.5%). Patients having high-risk EUTOS score were similar in both groups (38.4% vs. 37.6%). The patients presented in blast phase were higher in the study group as compared to control group (9.6% vs. 6.36%) but the differences were not statistically significant. Rates of achieving a hematological response at 3 months (85.1% vs. 86.89%) and the major molecular response at 18 months (54.3% vs. 60.16%) were almost similar in both groups. However, hematological toxicity, muscle cramps and gastritis were reported more in elderly patients. The outcome of CML patients in TKI era do not differ in elderly patients. However, toxicity profile was not significantly inferior in elderly patients.

Chronic myeloproliferative neoplasms in the elderly

This review focuses on the management of elderly patients with chronic myeloid leukemia and chronic myeloproliferative neoplasms, including polycythemia vera, essential thrombocythemia and primary myelofibrosis. Median age in these neoplasms is within the 6th decades of age. All new therapies can be done at any age without absolute contraindication. However, the selection of the precise therapy for the single patient is mandatory. For these reasons, an accurate definition of diagnosis and prognostication is necessary. Precision in disease definition and prognostication is definitively helpful for personalizing therapeutic approach.

Front-line imatinib treatment in children and adolescents with chronic myeloid leukemia: results from a phase III trial

A total of 156 patients (age range 1.3-18.0 years, median 13.2 years; 91 (58.3%) male) with newly diagnosed CML (N = 146 chronic phase (CML-CP), N = 3 accelerated phase (CML-AP), N = 7 blastic phase (CML-BP)) received imatinib up-front (300, 400, 500 mg/m², respectively) within a prospective phase III trial. Therapy response, progression-free survival, causes of treatment failure, and side effects were analyzed in 148 children and adolescents with complete data. Event-free survival rate by 18 months for patients in CML-CP (median follow-up time 25 months, range: 1-120) was 97% (95% CI, 94.2-99.9%). According to the 2006 ELN-criteria complete hematologic response by month 3, complete cytogenetic response (CCyR) by month 12, and major molecular response (MMR) by month 18 were achieved in 98, 63, and 59% of the patients, respectively. By month 36, 86% of the patients achieved CCyR and 74% achieved MMR. Thirty-eight patients (27%) experienced imatinib failure because of unsatisfactory response or intolerance (N = 9). In all, 28/148 patients (19%) underwent stem cell transplantation (SCT). In the SCT sub-cohort 2/23 patients diagnosed in CML-CP, 0/1 in CML-AP, and 2/4 in CML-BP, respectively, died of relapse (N = 3) or SCT-related complications (N = 2). This large pediatric trial extends and confirms data from smaller series that first-line imatinib in children is highly effective.

Long-term follow-up of de novo chronic phase chronic myelogenous leukemia patients on front-line imatinib

For the last 15years, imatinib mesylate (IM) has represented the gold standard treatment for chronic-phase chronic myelogenous leukemia (CP-CML); however, outcomes in the very long term remain unknown. We retrospectively analyzed the outcome of 418 IM first-line treated CP-CML patients followed in three reference centers over 15years in and outside of clinical trials, which is believed to represent the "real-life" care of such patients. Molecular analyses were standardized over the years. In case of intolerance or resistance or IM cessation and progression, all clinical data were collected and analyzed. After a median follow-up of 83 months (range 1-194), the overall survival (OS) rates were 91% and 82%, the progression-free survival (PFS) rates were 88.5% and 81%, and the event-free survival rates, including switching to another tyrosine kinase inhibitor, were 65% and 51%, respectively, at 5 and 10years. Thirteen patients (3%) entered blast crisis (BC) with a median survival of 2.2years after BC onset. Forty-nine percent of patients were in major molecular response at 1 year. Univariate analysis failed to detect any impact on survival of molecular response at 3 and 6 months. Sokal score had a significant impact on OS and PFS in a Cox model. Age had a significant impact on OS and PFS, mainly due to deaths in elderly patients unrelated to CML. Overall, 21% of patients reached a stable (≥1 year) molecular response 4 (MR4) and 6.5% reached MR4.5. At last follow-up, 63% of patients were still on IM and 19% were in treatment-free remission. We conclude that IM is an excellent therapeutic option providing impressive long-term OS rates.

Impact of age on efficacy and toxicity of nilotinib in patients with chronic myeloid leukemia in chronic phase: ENEST1st subanalysis

Purpose

Achievement of deep molecular response with a tyrosine kinase inhibitor in patients with chronic myeloid leukemia (CML) is required to attempt discontinuation of therapy in these patients. The current subanalysis from the Evaluating Nilotinib Efficacy and Safety in Clinical Trials as First-Line Treatment (ENEST1st) study evaluated whether age has an impact on the achievement of deeper molecular responses or safety with frontline nilotinib in patients with CML.

Methods

ENEST1st is an open-label, multicenter, single-arm, prospective study of nilotinib 300 mg twice daily in patients with newly diagnosed CML in chronic phase. The patients were stratified into the following 4 groups based on age: young (18–39 years), middle age (40–59 years), elderly (60–74 years), and old (≥75 years). The primary end point was the rate of molecular response 4 ([MR⁴] BCR–ABL1 ≤0.01% on the international scale) at 18 months from the initiation of nilotinib.

Results

Of the 1091 patients enrolled, 1089 were considered in the analysis, of whom, 23% (n = 243), 45% (n = 494), 27% (n = 300), and 5% (n = 52) were categorized as young, middle age, elderly, and old, respectively. At 18 months, the rates of MR⁴ were 33.9% (95% confidence interval [CI], 27.8–40.0%) in the young, 39.6% (95% CI, 35.3–44.0%) in the middle-aged, 40.5% (95% CI, 34.8–46.1%) in the elderly, and 35.4% (95% CI, 21.9–48.9%) in the old patients. Although the incidence of adverse events was slightly different, no new specific safety signals were observed across the 4 age groups.

Conclusions

This subanalysis of the ENEST1st study showed that age did not have a relevant impact on the deep molecular response rates associated with nilotinib therapy in newly diagnosed patients with CML and eventually on the eligibility of the patients to attempt treatment discontinuation.

Curcumin inhibits in vitro and in vivo chronic myelogenous leukemia cells growth: a possible role for exosomal disposal of miR-21

Exosomes are nanosize vesicles released from cancer cells containing microRNAs that can influence gene expression in target cells. Curcumin has been shown to exhibit antitumor activities in a wide spectrum of human cancer. The addition of Curcumin, to Chronic Myelogenous Leukemia (CML) cells, caused a dose-dependent increase of PTEN, target of miR-21. Curcumin treatment also decreased AKT phosphorylation and VEGF expression and release. Colony formation assays indicated that Curcumin affects the survival of CML cells. Some observation suggest a possible cellular disposal of miRNAs by exosomes. To elucidate if Curcumin caused a decrease of miR-21 in CML cells and its packaging in exosomes, we analyzed miR-21 content in K562 and LAMA84 cells and exosomes, after treatment with Curcumin. Furthermore, we showed that addition of Curcumin to CML cells caused a downregulation of Bcr-Abl expression through the cellular increase of miR-196b.The effects of Curcumin was then investigated on a CML xenograft in SCID mice. We observed that animals treated with Curcumin, developed smaller tumors compared to mice control. Real time PCR analysis showed that exosomes, released in the plasma of the Curcumin-treated mice, were enriched in miR-21 with respect control. Taken together, our results suggested that a selective packaging of miR-21 in exosomes may contribute to the antileukemic effect of Curcumin in CML.

Management of Elderly Patients with Newly Diagnosed Chronic Myeloid Leukemia in the Accelerated or Blastic Phase

In the elderly population, the accelerated and blastic phases of chronic myeloid leukemia (CML) are difficult to treat, not just because of the higher chance of acquired mutations than in younger individuals, but because of additional associated co-morbidities. Tyrosine kinase inhibitors are well-established in the treatment of the chronic phase of CML, and their use in advanced phases is ever-increasing. Elderly patients who are still eligible candidates for transplant can undergo reduced-intensity transplants from related or unrelated donors after reverting to chronic phase. Post-transplantation, these patients require adequate monitoring and therapy to prevent relapses. Newer modalities of treatment or interventions are urgently required in this complex group of patients.

The impact of comorbidity on health-related quality of life in elderly patients with chronic myeloid leukemia

The primary objective of this study was to investigate whether the presence of comorbidities was associated with a lower health-related quality of life (HRQOL) in elderly patients with chronic myeloid leukemia (CML). A sample of 174 CML patients aged 60 years or above was analyzed. HRQOL was assessed with the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). A number of pre-selected sociodemographic and disease-related factors were considered as potential confounding factors for the association between comorbidity and HRQOL. Mean age of the 174 patients analyzed was 70 years (range 60-87 years) and 55 % were male. Overall, 111 patients (64 %) reported at least one comorbidity. Analysis stratified by age group category showed a greater proportion of patients with comorbidities in the older sub-group population (≥70 years) compared to younger patients (60 to 69 years). Differences in HRQOL outcomes between patients with no comorbidity at all and those with two or more comorbid conditions were at least twice the magnitude of a clinically meaningful difference in all the physical and mental health scales of the SF-36. In multivariate analysis, after adjusting for key confounding factors, the following scales were significantly lower in those with comorbidity: general health (p < 0.001), bodily pain (p < 0.001), physical functioning (p = 0.002), and vitality (p = 0.002). Assessing comorbidity in elderly patients with CML is important to facilitate identification of those most in need of HRQOL improvements.

Factors influencing long-term efficacy and tolerability of bosutinib in chronic phase chronic myeloid leukaemia resistant or intolerant to imatinib

The dual SRC/ABL1 tyrosine kinase inhibitor bosutinib is indicated for adults with Ph+ chronic myeloid leukaemia (CML) resistant/intolerant to prior therapy. This analysis of an ongoing phase 1/2 study (NCT00261846) assessed effects of baseline patient characteristics on long‐term efficacy and safety of bosutinib 500 mg/day in adults with imatinib (IM)‐resistant (IM‐R; n = 196)/IM‐intolerant (IM‐I; n = 90) chronic phase (CP) CML. Median treatment duration was 24·8 months (median follow‐up, 43·6 months). Cumulative major cytogenetic response (MCyR) rate [95% confidence interval (CI)], was 59% (53–65%); Kaplan‐Meier (KM) probability of maintaining MCyR at 4 years was 75% (66–81%). Cumulative incidence of on‐treatment progression/death at 4 years was 19% (95% CI, 15–24%); KM 2‐year overall survival was 91% (87–94%). Significant baseline predictors of both MCyR and complete cytogenetic response (newly attained/maintained from baseline) at 3 and 6 months included prior IM cytogenetic response, baseline MCyR, prior interferon therapy and <6 months duration from diagnosis to IM treatment initiation and no interferon treatment before IM. The most common adverse event (AE) was diarrhoea (86%). Baseline bosutinib‐sensitive BCR‐ABL1 mutation was the only significant predictor of grade 3/4 diarrhoea; no significant predictors were identified for liver‐related AEs. Bosutinib demonstrates durable efficacy and manageable toxicity in IM‐R/IM‐I CP‐CML patients.

Accelerated phase chronic myeloid leukemia: evaluation of clinical criteria as predictors of survival, major cytogenetic response and progression to blast phase

Background

Published criteria defining the accelerated phase in chronic myeloid leukemia are heterogeneous and little is known about predictors of poor outcome.

Methods

This is a retrospective study of 139 subjects in the accelerated phase of chronic myeloid leukemia treated with imatinib at a single center in Brazil. The objective was to identify risk factors for survival, major cytogenetic response and progression to blast phase in this population. The factors analyzed were: blasts 10–29%, basophils ≥ 20%, platelets > 1 × 10⁶/μL or <1 × 10⁵/μL and white blood cells > 1 × 10⁵/μL in the peripheral blood, as well as clonal evolution, splenomegaly, hemoglobin < 10 g/dL, time between diagnosis of chronic myeloid leukemia and imatinib treatment, and hematologic toxicity.

Results

Risk factors for poor survival in multivariate analysis were Grades 3–4 hematologic toxicity (p-value = 0.001), blasts 10–29% (p-value = 0.023), and hemoglobin < 10 g/dL (p-value = 0.04). Risk factors for not achieving major cytogenetic response were blasts 10–29% (p-value = 0.007), hemoglobin < 10 g/dL (p-value = 0.001), and previous use of interferon (p-value = 0.032). Risk factors for progression to the blast phase were hemoglobin < 10 g/dL (p-value = 0.005), basophils ≥ 20% (p-value = 0.023), and time from diagnosis of chronic myeloid leukemia to imatinib treatment > 12 months (p-value = 0.030).

Conclusion

These data indicate that patients with the above risk factors have a worse prognosis. This information can guide the therapy to be used.

First-line treatment of newly diagnosed elderly patients with chronic myeloid leukemia: current and emerging strategies

Chronic myeloid leukemia (CML) is a disease of the hematopoietic stem cell characterized by a median age at diagnosis of 60-65 years according to most epidemiologic registries. Prior to the tyrosine kinase inhibitor (TKI) era, older age was considered an adverse prognostic factor and was included in two of the most used scoring systems for CML, the Sokal score and the Euro score. Moreover, older age was generally considered a limitation for the use of allogeneic stem-cell transplantation, given the higher toxicity observed. After the introduction of TKIs, age lost much of its prognostic impact in patients in chronic phase (CP), and the EUTOS score, developed in patients treated with imatinib, did not identify age as a risk variable. However, most CML patients require life-long treatment; therefore, as patients age while taking a TKI, the complexity of the management of elderly patients may increase over time. To date, imatinib, the first TKI introduced, and two second-generation TKIs, nilotinib and dasatinib, have been approved in most Western countries for the first-line treatment of CML. These drugs differ in terms of efficacy, safety, and costs; therefore, knowledge of their characteristics is extremely relevant for optimal management of elderly CML patients. We reviewed the impact of age on the first-line treatment of CP CML patients in the TKI era, considering the epidemiology of the disease, the role of comorbidities, and analyzing data from population-based studies and clinical trials.

Overcoming therapy failure in elderly patients with chronic myeloid leukemia

SUMMARY 

Chronic myeloid leukemia (CML) affects mainly older adults, as median age at diagnosis is 60–65 years. For a long time, survival of elderly CML patients has been shorter compared with younger patients. With the advent of the first tyrosine kinase inhibitor (TKI), imatinib, long-term outcome has significantly improved, including in the elderly, with rates of cytogenetic and molecular responses roughly equal to those attained in the young, as well as manageable toxicity. More recently, second-generation (dasatinib, nilotinib and bosutinib) and third-generation (ponatinib) TKIs were employed in CML patients failing imatinib or other front-line treatments. Despite a shorter follow-up, these TKIs showed remarkable activity in elderly patients. This review focuses on the therapeutic strategies to prevent and overcome treatment failure in elderly CML patients.

Older patients with chronic myeloid leukemia (≥65 years) profit more from higher imatinib doses than younger patients: a subanalysis of the randomized CML-Study IV

The impact of imatinib dose on response rates and survival in older patients with chronic myeloid leukemia in chronic phase has not been studied well. We analyzed data from the German CML-Study IV, a randomized five-arm treatment optimization study in newly diagnosed BCR-ABL-positive chronic myeloid leukemia in chronic phase. Patients randomized to imatinib 400 mg/day (IM400) or imatinib 800 mg/day (IM800) and stratified according to age (≥65 years vs. <65 years) were compared regarding dose, response, adverse events, rates of progression, and survival. The full 800 mg dose was given after a 6-week run-in period with imatinib 400 mg/day. The dose could then be reduced according to tolerability. A total of 828 patients were randomized to IM400 or IM800. Seven hundred eighty-four patients were evaluable (IM400, 382; IM800, 402). One hundred ten patients (29 %) on IM400 and 83 (21 %) on IM800 were ≥65 years. The median dose per day was lower for patients ≥65 years on IM800, with the highest median dose in the first year (466 mg/day for patients ≥65 years vs. 630 mg/day for patients <65 years). Older patients on IM800 achieved major molecular remission and deep molecular remission as fast as younger patients, in contrast to standard dose imatinib with which older patients achieved remissions much later than younger patients. Grades 3 and 4 adverse events were similar in both age groups. Five-year relative survival for older patients was comparable to that of younger patients. We suggest that the optimal dose for older patients is higher than 400 mg/day. ClinicalTrials.gov identifier: NCT00055874

Age influences initial dose and compliance to imatinib in chronic myeloid leukemia elderly patients but concomitant comorbidities appear to influence overall and event-free survival

We applied Charlson comorbidity index (CCI) stratification on a large cohort of chronic myeloid leukemia (CML) very elderly patients (>75 years) treated with imatinib, in order to observe the impact of concomitant diseases on both compliance and outcome. One hundred and eighty-one patients were recruited by 21 Italian centers. There were 95 males and 86 females, median age 78.6 years (range 75-93.6). According to Sokal score, 106 patients were classified as intermediate risk and 55 as high risk (not available in 20 patients). According to CCI stratification, 71 patients had score 0 and 110 a score ≥ 1. Imatinib standard dose was reduced at start of therapy (200-300 mg/day) in 68 patients independently from the evaluation of baseline comorbidities, but based only on physician judgement: 43.6% of these patients had score 0 compared to 34% of patients who had score ≥ 1. Significant differences were found in terms of subsequent dose reduction (39% of patients with score 0 compared to 53% of patients with score ≥ 1) and in terms of drug discontinuation due to toxicity (35% of patients with score 0 vs 65% of patients with score ≥ 1). We did not find significant differences as regards occurrence of hematologic side effects, probably as a consequence of the initial dose reduction: 39% of patients with score 0 experienced grade 3/4 hematologic toxicity (most commonly anemia) compared to 42% of patients with score ≥ 1. Independently from the initial dose, comorbidities again did not have an impact on development of grade 3/4 non-hematologic side effects (most commonly skin rash, muscle cramps and fluid retention): 62% of patients with score 0 compared to 52.5% of patients with score ≥ 1. Notwithstanding the reduced dose and the weight of comorbidities we did not find significant differences but only a trend in terms of efficacy: 66% of patients with score 0 achieved a CCyR compared to 54% of patients with score ≥ 1. Comorbidities appeared to have an impact on median OS (40.8 months for patients with score 0 vs 20.16 months for patients with score ≥ 1) on EFS and on non-CML death rate. Our results suggest that treatment of very elderly CML patients might be influenced by personal physician perception: evaluation at baseline of comorbidities according to CCI should improve initial decision-making in this subset of patients.

Comorbidities and polypharmacy impact on complete cytogenetic response in chronic myeloid leukaemia elderly patients

BACKGROUND

In older patients comorbidity and polypharmacy can significantly influence the success of the treatment, as well as the cognitive and psycho-social aspects. A significant proportion of chronic myeloid leukaemia (CML) patients are "elderly": in the past the aim of therapy in this subset of patients was only to contain the leukaemic mass, but nowadays, with the advent of the protein-tyrosine kinase inhibitors, also elderly patients can access these treatments. We want to assess if even old CML patients, with a correct geriatric evaluation, can be successfully treated with protein-tyrosine kinase inhibitors.

METHODS

A complete geriatric evaluation in 16 old CML patients aged >65years treated with TKI was performed in order to assess the comorbidity, the polypharmacy and the cognitive, physical and psychological states. The Charlson comorbity index (CCI) and the polypharmacy were correlated to the obtained cytogenetic response. Seven scales of geriatric evaluation were used to assess the autonomy of patients before they were included into the study.

RESULTS

In our cohort of elderly patients treated with imatinib, comorbidities and polypharmaco-therapy demonstrated an influence on TKI therapeutic success. In fact, the majority of complete cytogenetic response was obtained by patients who presented a low score of CCI and did not take any other drugs other than TKI.

CONCLUSION

Also old chronic myeloid leukaemia patients can benefit from TKI treatment if a good cooperation between the haematologist and the geriatrician is established.

Younger patients with chronic myeloid leukemia do well in spite of poor prognostic indicators: results from the randomized CML study IV

Since the advent of tyrosine kinase inhibitors, the impact of age on outcome of chronic myeloid leukemia (CML) patients has changed. We therefore analyzed patients from the randomized CML study IV to investigate disease manifestations and outcome in different age groups. One thousand five hundred twenty-four patients with BCR-ABL-positive chronic phase CML were divided into four age groups: (1) 16–29 years, n = 120; (2) 30–44 years, n = 383; (3) 45–59 years, n = 495; and (4) ≥60 years, n = 526. Group 1 (adolescents and young adults (AYAs)) presented with more aggressive disease features (larger spleen size, more frequent symptoms of organomegaly, higher white blood count, higher percentage of peripheral blasts and lower hemoglobin levels) than the other age groups. In addition, a higher rate of patients with BCR-ABL transcript levels >10 % on the international scale (IS) at 3 months was observed. After a median observation time of 67.5 months, no inferior survival and no differences in cytogenetic and molecular remissions or progression rates were observed. We conclude that AYAs show more aggressive features and poor prognostic indicators possibly indicating differences in disease biology. This, however, does not affect outcome.

Population level survival of patients with chronic myelocytic leukemia in Germany compared to the US in the early 21st century

INTRODUCTION

The advent of tyrosine kinase inhibitors has produced 5-year survival of 90 + % for chronic myelocytic leukemia (CML) patients in clinical trials. However, population level survival has been lower, especially in older patients. Here, we examine survival of patients with CML in Germany and compare it to survival of patients in the United States (US).

METHODS

Data were extracted from the Surveillance, Epidemiology, and End Results database in the US and 11 cancer registries in Germany. Patients 15-69 years old diagnosed with CML were included in the analysis. Period analysis for 2002-2006 was used to provide the most up-to-date possible estimates of five-year relative survival.

RESULTS

Five-year relative survival was 68.7% overall in Germany and 72.7% in the US. Survival was higher in the US for all age groups except for ages 15-39 years, but the difference was only statistically significant for ages 50-59 years (at 67.5% vs 77.7% in Germany and the US, respectively). Survival decreased with age, ranging from 83.1% and 81.9%, respectively, in Germany and the US for patients 15-39 years old to 54.2% and 54.5%, respectively, in patients 65-69 years old. Survival increased between 2002 and 2006 by 12.0% points in Germany and 17.1% points in the US.

CONCLUSIONS

Five-year survival estimates were higher in the US than in Germany overall, but the difference was only significant for ages 50-59 years. Survival did not equal that seen in clinical trials for either country, but strong improvement in survival was seen between 2002 and 2006.

Management options for refractory chronic myeloid leukemia: considerations for the elderly

Despite the excellent results obtained with standard-dose imatinib as first-line therapy for chronic myeloid leukemia in the chronic phase, one third of patients do not achieve an optimal response and require alternative therapies due to the emergence of drug resistance. Studies of resistance mechanisms, first tested in vitro and then in vivo, have driven the development of second-generation tyrosine kinase inhibitors (TKIs), dasatinib and nilotinib. These agents have been proven effective in a large number of patients resistant to imatinib and are also effective in older patients. The use of second-generation TKIs in first-line treatment has increased the rate of cytogenetic and molecular responses and reduced the number of patients experiencing disease progression. In this review, we detail the various mechanisms of resistance and management options for refractory patients, in particular in older patients. No differences in terms of efficacy were reported in this subset of patients when treated with nilotinib or dasatinib after imatinib resistance. Results of trials that tested second-generation TKIs as first-line treatment showed similar results in older and younger patients.

Long-term safety and efficacy of imatinib mesylate (Gleevec®) in elderly patients with chronic phase chronic myelogenous leukemia: results of the AFR04 study

Data from registries suggest that the median age of chronic myelogenous leukemia (CML) patients is 10-15 years older than that of clinical trials. We conducted a prospective phase II study to evaluate imatinib mesylate (IM, 400 mg daily) in newly diagnosed chronic phase CML (CP-CML) patients. Patients aged 70 years and over diagnosed with CP-CML within 12 months were eligible. Thirty patients were enrolled from April 2002 to October 2004. Median age was 74.8 years (range, 70-90). Male/female ratio was 1.72. At inclusion, comorbidities were reported in all but one patient, Cumulative Illness Rating Scale for Geriatrics comorbidity mean index was 1.47, and 66% of patients had cardiovascular disease. The median daily IM dose was 392 mg (range, 256-445). IM was interrupted in patients with severe comorbidities. Treatment discontinuation was observed in 36.6% of patients. Cumulative incidence of complete cytogenetic response was 71.4 and 78.5% at 12 and 24 months, respectively. A high level of sustained responses was observed in patients with mild or moderate comorbidities. Seven-year estimated overall survival was 80.8% (95% CI: 59.0-91.7). Two-thirds of the patients were still on long-term therapy at cut-off, and no patients had died from progression. This trial was registered at http://www.clinicaltrials.gov as # NCT00219765.

Tyrosine kinase inhibitors in acute and chronic leukemias

INTRODUCTION

Since the initial approval of imatinib much has been learned about its resistance mechanisms, and efforts have continued to improve upon BCR-ABL tyrosine kinase inhibitor therapy. Targeted therapy with TKIs has continued to be an area of active research and development in the care of acute and chronic leukemia patients.

AREAS COVERED

This article reviews current approved and investigational TKI treatments for chronic myelogenous leukemia (CML), Philadelphia-chromosome positive acute lymphoblastic leukemia (Ph + ALL) and acute myelogenous leukemia (AML).

EXPERT OPINION

There are now more potent BCR-ABL TKIs approved, which allow for additional options when determining front-line and second-line CML and Ph + ALL treatments. The T315I mutation is an ever-present challenge. Ponatinib, a pan BCR-ABL TKI, while still under investigation, is very hopeful with its ability to overcome T315I mutations in resistant CML and Ph + ALL patients. Because nilotinib and dasatinib have not been directly compared, at present we recommend selecting one or the other based on the side-effect profile, drug interactions, patient comorbidities, and mutational status. FLT-3 inhibition is of particular interest in AML patients with FLT-3 internal tandem duplication mutations; this type of targeted therapy continues to be studied.

Analysis of outcomes in adolescents and young adults with chronic myelogenous leukemia treated with upfront tyrosine kinase inhibitor therapy

BACKGROUND

Outcomes in chronic myeloid leukemia have improved with tyrosine kinase inhibitor treatment. However, little is known about outcomes of chronic myeloid leukemia in adolescent and young adult patients.

DESIGN AND METHODS

We reviewed all 468 chronic myeloid leukemia patients treated at our institution with tyrosine kinase inhibitors as initial therapy: imatinib (n=281), nilotinib (n=98) or dasatinib (n=89).

RESULTS

Median age was 47 years, median follow up 71 months and median treatment time with initial tyrosine kinase inhibitors 48 months. Adolescent and young adult was defined as aged 15-29 years. Sixty-one adolescent and young adult patients were identified. The only significant differences between adolescent and young adult and older patients were incidence of splenomegaly and distribution in Sokal risk groups. Only 3 adolescent and young adult patients have died. Rates of complete cytogenetic, major molecular and complete molecular response were significantly higher in older patients compared to adolescent and young adult patients, with a favorable trend in event-free survival for older patients. Transformation-free and overall survival were similar for the two groups.

CONCLUSIONS

The unfavorable trend in outcome for adolescent and young adult patients with chronic myeloid leukemia is unexpected. Additional research in this population is required to better define outcomes, understand the cause of this difference, and to help make better treatment recommendations.

Frontline imatinib treatment of chronic myeloid leukemia: no impact of age on outcome, a survey by the GIMEMA CML Working Party

The median age of chronic myeloid leukemia (CML) patients is ∼ 60 years, and age is still considered an important prognostic factor, included in Sokal and EURO risk scores. However, few data are available about the long-term outcome of older patients treated with imatinib (IM) frontline. We analyzed the relationship between age and outcome in 559 early chronic-phase CML patients enrolled in 3 prospective clinical trials of Gruppo Italiano Malattie Ematologiche dell'Adulto CML Working Party, treated frontline with IM, with a median follow-up of 60 months. There were 115 older patients (≥ 65 years; 21%). The complete cytogenetic and major molecular response rates were similar in the 2 age groups. In older patients, event-free survival (55% vs 67%), failure-free survival (78% vs 92%), progression-free survival (62% vs 78%), and overall survival (75% vs 89%) were significantly inferior (all P < .01) because of a higher proportion of deaths that occurred in complete hematologic response, therefore unrelated to CML progression (15% vs 3%, P < .0001). The outcome was similar once those deaths were censored. These data show that response to IM was not affected by age and that the mortality rate linked to CML is similar in both age groups. This trial was registered at www.clinicaltrials.gov as #NCT00514488 and #NCT00510926.

Evaluation of tolerability and efficacy of imatinib mesylate in elderly patients with chronic phase CML: ELDERGLI study

Imatinib mesylate (IM) is the treatment of choice in patients with newly diagnosed chronic myeloid leukemia (CML), irrespectively of their age. Nevertheless, information regarding tolerability and responses in advanced-age patients, a subgroup in which co-morbidities and other factors may influence outcome, is scarce, since they were excluded from most clinical trials. In this observational study (ELDERGLI), information regarding demographics, concomitant medication, physical examination, performance status, hemogram, biochemistry, hematologic, cytogenetic and molecular responses, time to progression, adverse events (AE) and severe adverse events (SAE) were prospectively recorded in a series of 36 elderly patients with CML, with a median age of 76.6 years. Most patients had cardiovascular co-morbidities, especially hypertension. Regarding IM toxicity, around one third of patients required treatment interruptions because of adverse events, especially hematologic toxicity (66% of cases that needed dose interruptions). When analyzing non hematologic adverse events, the most frequent ones were superficial edemas and GI symptoms. Of note, 9 of patients experienced an infection episode during the follow-up, and 4 were diagnosed during the study period of another type of cancer. Finally, cardiovascular events were reported in 7 patients, most of them with prior cardiovascular risk factors. Regarding responses, after 12 months of imatinib therapy, the rate of complete hematologic response (CHR), complete cytogenetic response (CCyR) and major molecular response (MMolR) were 89%, 72% and 55% respectively. In summary, IM display, in advanced-age patients with chronic phase CML, an efficacy and safety profile comparable to younger patients.

"Real-life" results of front-line treatment with Imatinib in older patients (≥ 65 years) with newly diagnosed chronic myelogenous leukemia

The age role was evaluated in 117 consecutive patients with newly diagnosed CML at our Institution treated with front-line Imatinib from 9/02 to 3/08. Forty patients (34.1%) aged ≥ 65 years and 77 (65.9%) <65 years. Thirty-four older patients (85%) had at least 1 comorbidity versus 39 younger patients (50.6%) (p<0.001). Complete cytogenetic response (CCyR) was achieved in 34/40 older patients (85%) as compared to 69/77 younger patients (89.6%), without statistically significant differences. Severe (grades 3-4 WHO) hematological and extra-hematological toxicities were more common in older patients (p=0.02 and p=0.017, respectively). Rates of permanent Imatinib discontinuation and dose reduction to 300 mg or less were significantly higher in older patients (p=0.009 and p=0.001, respectively). In conclusion, Imatinib in older patients with newly diagnosed CML seems to have the same efficacy as in younger patients, but tends to be more toxic, leading to higher rates of discontinuation and dose reduction. To overcome this problem, future trials concerning best dosage in this subset of patients could be useful.

Predicting the response of CML patients to tyrosine kinase inhibitor therapy

Tyrosine kinase inhibitor (TKI) therapy has significantly changed the treatment paradigm for patients with chronic myeloid leukemia (CML). The first-generation inhibitor, imatinib, has demonstrated remarkable efficacy in most chronic-phase patients. Disease progression remains a significant risk for the first 2 to 3 years of TKI therapy, but the risk falls significantly thereafter. Early recognition of each individual's risk of progression may facilitate a customized approach to TKI therapy. Using such an approach, drug selection and treatment intensity would be adjusted on the basis of each patient's disease profile. Currently available prognostic indicators have limited value in the setting of the potent kinase inhibition afforded by TKIs. Furthermore, these indicators provide little guidance regarding optimal drug choice and dose intensity. In the future, assays that directly assess the efficacy of the protein-drug interaction, taking into account factors intrinsic to the patient and the amount of drug freely available in the plasma, are likely to be of greater value.

Age disparity in the dissemination of imatinib for treating chronic myeloid leukemia

BACKGROUND

Imatinib is a highly effective treatment for chronic myeloid leukemia. It was approved by the Food and Drug Administration in 2001 and thereafter rapidly became front-line therapy. This study characterized the prevailing chronic myeloid leukemia therapies in the United States and assessed the impact of imatinib on chronic myeloid leukemia survival and mortality rates in the general population.

METHODS

Investigators with the National Cancer Institute's Patterns of Care study reviewed medical records and queried physicians regarding therapy for 423 patients with chronic myeloid leukemia diagnosed in 2003 who were randomly selected from cancer registries in the Surveillance, Epidemiology, and End Results Program. Characteristics associated with the receipt of imatinib were documented, as were survival differences between those who received imatinib and those who did not. Population-based data were used to assess chronic myeloid leukemia survival and mortality rates in time periods before and after the introduction of imatinib.

RESULTS

Imatinib was administered to 76% of patients in the Patterns of Care study. Imatinib use was inversely associated with age: 90%, 75%, and 46% for patients ages 20 to 59 years, 60 to 79 years, and 80 or more years, respectively. Elderly patients who received imatinib survived significantly longer than those who did not. After adjusting for age, imatinib use did not vary significantly by race/ethnicity, socioeconomic status, urban/rural residence, presence of comorbid conditions, or insurance status. Overall, chronic myeloid leukemia survival in the Surveillance, Epidemiology, and End Results population improved, and mortality in the United States declined dramatically during the period when imatinib became widely available; these improvements diminished with increasing age.

CONCLUSION

Age disparities in treatment with imatinib likely contributed to worse survival for many elderly patients with chronic myeloid leukemia.