Estimated Savings After Stopping Tyrosine Kinase Inhibitor Treatment Among Patients With Chronic Myeloid Leukemia.

Importance: Patients with chronic myeloid leukemia (CML) who have a sustained deep molecular response using tyrosine kinase inhibitors (TKIs) can safely attempt to stop their use. As these medications are very costly, this change in treatment protocols may result in large savings. Objective: To estimate future savings from attempting to stop TKI use among patients with CML who have deep molecular response. Design, Setting, and Participants: A microsimulation model was developed for this decision analytical modeling study to estimate costs for US adults moving from using a TKI, to attempting discontinuation and then reinitiating TKI therapy, if clinically appropriate. Estimates were calculated for US patients who currently have CML and simulated newly diagnosed cohorts of patients over the next 30 years. Exposure: Attempting to stop using a TKI. Main Outcomes and Measures: Estimated savings after attempted discontinuation of TKI use. Results: A simulated population of individuals with CML in 2018 and future populations were created using estimates from the SEER*Explorer website. The median age at diagnosis was 66 years for men and 65 years for women. Between 2022 and 2052, the savings associated with eligible patients attempting discontinuation of TKI therapy was estimated at more than $30 billion among those currently diagnosed and over $15 billion among those who will develop CML in the future, for a total savings of over $54 billion by 2052 for drug treatment and polymerase chain reaction testing. The estimate is conservative as it does not account for complications and other health care-associated costs for patients continuing TKI therapy. Conclusions and Relevance: The findings of this decision analytical modeling study of patients with CML suggest that attempting discontinuation of TKI therapy could save over $54 billion during the next 30 years. Further education for patients and physicians is needed to safely increase the number of patients who can successfully attain treatment-free remission.

Assessment of Outcomes After Stopping Tyrosine Kinase Inhibitors Among Patients With Chronic Myeloid Leukemia: A Nonrandomized Clinical Trial.

IMPORTANCE: Tyrosine kinase inhibitors (TKIs) have been associated with improved survival of patients with chronic myeloid leukemia (CML) but are also associated with adverse effects, especially fatigue and diarrhea. Discontinuation of TKIs is safe and is associated with the successful achievement of treatment-free remission (TFR) for some patients. OBJECTIVE: To evaluate molecular recurrence (MRec) and patient-reported outcomes (PROs) after TKI discontinuation for US patients with CML. DESIGN, SETTING, AND PARTICIPANTS: The Life After Stopping TKIs (LAST) study was a prospective single-group nonrandomized clinical trial that enrolled 172 patients from 14 US academic medical centers from December 18, 2014, to December 12, 2016, with a minimum follow-up of 3 years. Participants were adults with chronic-phase CML whose disease was well controlled with imatinib, dasatinib, nilotinib, or bosutinib. Statistical analysis was performed from August 13, 2019, to March 23, 2020. INTERVENTION: Discontinuation of TKIs. MAIN OUTCOMES AND MEASURES: Molecular recurrence, defined as loss of major molecular response (BCR-ABL1 International Scale ratio >0.1%) by central laboratory testing, and PROs (Patient-Reported Outcomes Measurement Information System computerized adaptive tests) were monitored. Droplet digital polymerase chain reaction (ddPCR) was performed on samples with undetectable BCR-ABL1 by standard real-time quantitative polymerase chain reaction (RQ-PCR). RESULTS: Of 172 patients, 89 were women (51.7%), and the median age was 60 years (range, 21-86 years). Of 171 patients evaluable for molecular analysis, 112 (65.5%) stayed in major molecular response, and 104 (60.8%) achieved TFR. Undetectable BCR-ABL1 by either ddPCR or RQ-PCR at the time of TKI discontinuation (hazard ratio, 3.60; 95% CI, 1.99-6.50; P < .001) and at 3 months (hazard ratio, 5.86; 95% CI, 3.07-11.1; P < .001) was independently associated with MRec. Molecular recurrence for patients with detectable BCR-ABL1 by RQ-PCR was 50.0% (14 of 28), undetectable BCR-ABL1 by RQ-PCR but detectable by ddPCR was 64.3% (36 of 56), and undetectable BCR-ABL1 by both ddPCR and RQ-PCR was 10.3% (9 of 87) (P ≤ .001). Of the 112 patients in TFR at 12 months, 90 (80.4%) had a clinically meaningful improvement in fatigue, 39 (34.8%) had a clinically meaningful improvement in depression, 98 (87.5%) had a clinically meaningful improvement in diarrhea, 24 (21.4%) had a clinically meaningful improvement in sleep disturbance, and 5 (4.5%) had a clinically meaningful improvement in pain interference. Restarting a TKI resulted in worsening of PROs. CONCLUSIONS AND RELEVANCE: In this study, TKI discontinuation was safe, and 60.8% of patients remained in TFR. Discontinuation of TKIs was associated with improvements in PROs. These findings should assist patients and physicians in their decision-making regarding discontinuation of TKIs. Detectable BCR-ABL1 by RQ-PCR or ddPCR at the time of TKI discontinuation was associated with higher risk of MRec; clinical application of this finding should be confirmed in other studies. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02269267.

Molecular testing of chronic myeloid leukaemia in low resource areas.

Most cancer cases occur in areas of low resources. The diagnosis, treatment and monitoring of cancers is especially challenging in these locations. Unique partnerships exist between non-profit organisations and pharmaceutical companies to provide free drugs to CML patients throughout the world if the diagnosis can be rigorously and unambiguously established. But there lies the rub: How do you perform molecular diagnostics in areas where even electricity is unreliable? Here we describe the evolution of testing patients from low resource areas, which, when merged with a remarkable effort to bring tyrosine kinase inhibitors to patients across the globe, have led to survival outcomes similar to cases in industrialised countries.

Ultra-accurate Duplex Sequencing for the assessment of pretreatment ABL1 kinase domain mutations in Ph+ ALL.

Mutations of ABL1 are the dominant mechanism of relapse in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL). We performed highly accurate Duplex Sequencing of exons 4-10 of ABL1 on bone marrow or peripheral blood samples from 63 adult patients with previously untreated Ph + ALL who received induction with intensive chemotherapy plus a BCR-ABL1 TKI. We identified ABL1 mutations prior to BCR-ABL1 TKI exposure in 78% of patients. However, these mutations were generally present at extremely low levels (median variant allelic frequency 0.008% [range, 0.004%-3.71%] and did not clonally expand and lead to relapse in any patient, even when the pretreatment mutation was known to confer resistance to the TKI received. In relapse samples harboring a TKI-resistant ABL1 mutation, the corresponding mutation could not be detected pretreatment, despite validated sequencing sensitivity of Duplex Sequencing down to 0.005%. In samples under the selective pressure of ongoing TKI therapy, we detected low-level, emerging resistance mutations up to 5 months prior to relapse. These findings suggest that pretreatment ABL1 mutation assessment should not guide upfront TKI selection in Ph + ALL, although serial testing while on TKI therapy may allow for early detection of clinically actionable resistant clones.

Meeting the needs of CML patients in resource-poor countries.

Subsequent to the development and global availability of BCR/ABL-targeted tyrosine kinase inhibitors (TKIs), the prognosis of patients with chronic myeloid leukemia (CML), at least those in the chronic phase, has markedly improved, and in the developed world, the average lifespan of these patients is now close to that of age- and sex-matched subjects without the disease. However, the situation in low- and middle-income countries (LMICs) may not be so rosy. Many important differences in hematological cancers, including CML, have been highlighted in various publications in LMICs vs developed countries. These include differences in incidence and prevalence rates, age and stage of disease at diagnosis, response rates, and survival. Some of the possible reasons proposed for these are varying socioeconomic milieu (impacting availability of effective drugs and essential monitoring), environmental factors (mainly exposure to viral infections and pesticides), nutritional factors with interplay of malnutrition and diet on drug absorption and blood levels, and possible unknown genetic factors. Although generic first-generation TKIs (imatinib) are available in many parts of the world, several challenges remain in providing optimal treatment to patients with CML in resource-poor countries. Some of these include availability of optimal and high-quality BCR/ABL testing, availability and expense related to use of second- and third-generation TKIs (nilotinib, dasatinib, bosutinib, and ponatinib) and hematopoietic stem cell transplantation, issues with compliance and toxicities of drugs, and ensuring a minimal standard-of-care treatment and monitoring for every patient diagnosed with CML. For the purpose of this article, the more objective country label-LMIC-coined by the World Bank will be used (gross national income per capita between $1026 and $3995; World Bank, June 2019). Some of these issues will be discussed in this article in greater detail by experts in the field in 3 different but interconnected sections.

Recommendations for the assessment and management of measurable residual disease in adults with acute lymphoblastic leukemia: A consensus of North American experts.

Measurable residual disease (MRD) that persists after initial therapy is a powerful predictor of relapse and survival in acute lymphoblastic leukemia (ALL). However, the optimal use of this information to influence therapeutic decisions is controversial. Herein, we comprehensively review the role of MRD assessment in adults with ALL, including methods to quantify residual leukemia cells during remission, prognostic impact of MRD across ALL subtypes, and available therapeutic approaches to eradicate MRD. This review presents consensus statements and provides an evidence-based framework for practicing hematologists and oncologists to use MRD information to make rational treatment decisions in adult patients with ALL.

Multigene Measurable Residual Disease Assessment Improves Acute Myeloid Leukemia Relapse Risk Stratification in Autologous Hematopoietic Cell Transplantation.

We report here the largest study to date of adult patients with acute myeloid leukemia (AML) tested for measurable residual disease (MRD) at the time of autologous hematopoietic cell transplantation (auto-HCT). Seventy-two adult patients who underwent transplantation between 2004 and 2013 at a single academic medical center (University of California San Francisco) were eligible for this retrospective study based on availability of cryopreserved granulocyte colony-stimulating factor (GCSF)-mobilized autologous peripheral blood progenitor cell (PBPC) leukapheresis specimens ("autografts"). Autograft MRD was assessed by molecular methods (real-time quantitative PCR [RQ-PCR] for Wilms tumor 1 (WT1) alone or a multigene panel) and by multiparameter flow cytometry (MPFC). WT1 RQ-PCR testing of the autograft had low sensitivity for relapse prediction (14%) and a negative predictive value of 51%. MPFC failed to identify MRD in any of 34 autografts tested. Combinations of molecular MRD assays, however, improved prediction of post-auto-HCT relapse. In multivariate analysis of clinical variables, including age, gender, race, cytogenetic risk category, and CD34+ cell dose, only autograft multigene MRD as assessed by RQ-PCR was statistically significantly associated with relapse. One year after transplantation, only 28% patients with detectable autograft MRD were relapse free, compared with 67% in the MRD-negative cohort. Multigene MRD, while an improvement on other methods tested, was however suboptimal for relapse prediction in unselected patients, with specificity of 83% and sensitivity of 46%. In patients with known chromosomal abnormalities or mutations, however, better predictive value was observed with no relapses observed in MRD-negative patients in the first year after auto-HCT compared with 83% incidence of relapse in the MRD-positive patients (hazard ratio, 12.45; P = .0016). In summary, increased personalization of MRD monitoring by use of a multigene panel improved the ability to risk stratify patients for post-auto-HCT relapse. WT1 RQ-PCR and flow cytometric assessment for AML MRD in autograft samples had limited value for predicting relapse after auto-HCT. We demonstrate that cryopreserved autograft material presents unique challenges for AML MRD testing because of the masking effects of previous GCSF exposure on gene expression and flow cytometry signatures. In the absence of information regarding diagnostic characteristics, sources other than GCSF-stimulated PBSC leukapheresis specimens should be considered as alternatives for MRD testing in AML patients undergoing auto-HCT.

Is cure for chronic myeloid leukemia possible in the tyrosine kinase inhibitors era?

PURPOSE OF REVIEW: The advent of tyrosine kinase inhibitors (TKI) has remarkably changed the treatment of chronic myeloid leukemia (CML). Patients treated in chronic phase can enjoy an expected survival similar to the general population. In the last few years we have found that some patients with an excellent therapeutic response can have their TKI discontinued and still remain in molecular remission. RECENT FINDINGS: The fact that some patients can apparently have their therapy discontinued, and stay in remission for more than 2 years, is surprising, as in-vitro work suggests the CML cell is dependent on BCR-ABL signaling and mathematical models predict that extinction of the CML stem cell reservoir will take decades of therapy. However, given that unopposed BCR-ABL causes progression and CML cells can have a rather long latency (e.g., Hiroshima survivors), it may be some time until we can be completely assured that discontinuation is without risk. SUMMARY: If we can safely discontinue TKI in some patients, it will have a profound effect on both the strategy and medical economics of CML therapy. A key future finding will be factor(s) that predict which patients can be discontinued without relapse, thus targeting only the patients where discontinuation will be successful.

Cost-effectiveness of the sequential application of tyrosine kinase inhibitors for the treatment of chronic myeloid leukemia.

Several tyrosine kinase inhibitors (TKIs) are approved for chronic myeloid leukemia (CML) therapy. We evaluated the long-term cost-effectiveness of seven sequential therapy regimens for CML in Austria. A cost-effectiveness analysis was performed using a state-transition Markov model. As model parameters, we used published trial data, clinical, epidemiological and economic data from the Austrian CML registry and national databases. We performed a cohort simulation over a life-long time-horizon from a societal perspective. Nilotinib without second-line TKI yielded an incremental cost-utility ratio of 121,400 €/quality-adjusted life year (QALY) compared to imatinib without second-line TKI after imatinib failure. Imatinib followed by nilotinib after failure resulted in 131,100 €/QALY compared to nilotinib without second-line TKI. Nilotinib followed by dasatinib yielded 152,400 €/QALY compared to imatinib followed by nilotinib after failure. Remaining strategies were dominated. The sequential application of TKIs is standard-of-care, and thus, our analysis points toward imatinib followed by nilotinib as the most cost-effective strategy.

Effectiveness and Cost-Effectiveness of Sequential Treatment of Patients with Chronic Myeloid Leukemia in the United States: A Decision Analysis.

Currently several tyrosine kinase inhibitors (TKIs) are approved for treatment of chronic myeloid leukemia (CML). Our goal was to identify the optimal sequential treatment strategy in terms of effectiveness and cost-effectiveness for CML patients within the US health care context. We evaluated 18 treatment strategies regarding survival, quality-adjusted survival, and costs. For model parameters, the literature data, expert surveys, registry data, and economic databases were used. Evaluated strategies included imatinib, dasatinib, nilotinib, bosutinib, ponatinib, stem-cell transplantation (SCT), and chemotherapy. We developed a Markov state-transition model, which was analyzed as a cohort simulation over a lifelong time horizon with a third-party payer perspective and discount rate of 3%. Remaining life expectancies ranged from 5.4 years (3.9 quality-adjusted life years (QALYs)) for chemotherapy treatment without TKI to 14.4 years (11.1 QALYs) for nilotinib→dasatinib→chemotherapy/SCT. In the economic evaluation, imatinib→chemotherapy/SCT resulted in an incremental cost-utility ratio (ICUR) of $171,700/QALY compared to chemotherapy without TKI. Imatinib→nilotinib→chemotherapy/SCT yielded an ICUR of $253,500/QALY compared to imatinib→chemotherapy/SCT. Nilotinib→dasatinib→chemotherapy/SCT yielded an ICUR of $445,100/QALY compared to imatinib→nilotinib→chemotherapy/SCT. All remaining strategies were excluded due to dominance of the clinically superior strategies. Based on our analysis and current treatment guidelines, imatinib→nilotinib→chemotherapy/SCT and nilotinib→dasatinib→chemotherapy/SCT can be considered cost-effective for patients with CML, depending on willingness-to-pay.

Systematic assessment of decision-analytic models for chronic myeloid leukemia.

BACKGROUND: Several tyrosine kinase inhibitors (TKIs) are approved for the treatment of chronic myeloid leukemia (CML). Decision-analytic modeling can help to extrapolate data from short-term clinical trials and also consider quality of life when evaluating different treatment strategies. OBJECTIVE: Our goal was to describe and analyze the structural and methodological approaches of published decision-analytic models for various treatment strategies in CML and to derive recommendations for the development of future CML models. DATA SOURCES: We performed a systematic literature search in electronic databases (MEDLINE/PreMEDLINE, EconLit, EMBASE, NHS EED, and Tuft's CEA Registry) to identify published studies evaluating CML treatment strategies using mathematical models. The search was updated in August 2013. STUDY SELECTION: The models were required to compare different treatment strategies in relation to relevant clinical and patient-relevant health outcomes [e.g., life-years gained, quality-adjusted life-years] over a defined time horizon and population. STUDY APPRAISAL AND SYNTHESIS METHODS: We used standardized forms for data extraction, description of study design, methodological framework, and data sources for each model. RESULTS: We identified 18 different decision-analytic modeling studies. Of these, 17 included economic evaluations. Modeling approaches included decision trees, Markov cohort models, state-transition models with individual (Monte Carlo) simulations, and mathematical equations. Analytic time horizons ranged from 2 years to a lifetime. Treatment strategies compared included bone marrow or stem cell transplantation, conventional chemotherapy, interferon-α, and TKIs. Only one model evaluated a second-generation TKI. Most models did not report a model validation. All models conducted deterministic sensitivity analyses and four reported a probabilistic sensitivity analysis. LIMITATIONS: Articles that were not published in English or German were not included in this review. Our literature search was restricted to published full-text articles in certain databases. Therefore, publications that met our inclusion criteria but were published in different databases, different languages, or as abstracts only may have been missed. CONCLUSIONS: While several well-designed models of CML treatment strategies exist, there remains a need for the assessment of the long-term efficacy and cost effectiveness of novel treatment options such as second-generation TKIs. Additionally, these models should be validated using independent data.

Medical decision analysis for first-line therapy of chronic myeloid leukemia.

Several tyrosine kinase inhibitors (TKIs) are approved for the treatment of chronic myeloid leukemia (CML). Our goal was to develop a clinical decision-analytic model for evaluation of the long-term effectiveness of different therapy regimens. We developed a Markov cohort model with a lifelong time horizon for first-line treatment with imatinib, dasatinib or nilotinib. Seven strategies including combinations of TKIs, chemotherapy and stem cell transplant were evaluated. The model was parameterized using published trial data, the Austrian CML registry and practice patterns estimated by experts. Health outcomes evaluated were life-years (LYs) and quality-adjusted LYs (QALYs). Based on our decision analysis, dasatinib following nilotinib failure was the most effective treatment in terms of LYs (19.8 LYs) and QALYs (16.1 QALYs). Sensitivity analyses showed that the ranking of strategies was mostly influenced by the duration of first- and second-line therapies. Our results may support decision-making regarding the sequential application of TKIs.

The case for early detection.

Early detection represents one of the most promising approaches to reducing the growing cancer burden. It already has a key role in the management of cervical and breast cancer, and is likely to become more important in the control of colorectal, prostate and lung cancer. Early-detection research has recently been revitalized by the advent of novel molecular technologies that can identify cellular changes at the level of the genome or proteome, but how can we harness these new technologies to develop effective and practical screening tests?