Treatment patterns and healthcare resource utilization in patients with FLT3-mutated and wild-type acute myeloid leukemia: A medical chart study

Treatment Patterns and FLT3 Mutation Testing Among Patients with Acute Myeloid Leukemia in China: A Retrospective Observational Study

Introduction

For acute myeloid leukemia (AML), prognosis is particularly poor in patients harboring FMS-like tyrosine kinase 3 (FLT3) gene mutations, though routine screening for these mutations at diagnosis has been shown to be insufficient. The understanding of the impact of FLT3 mutations on treatment decisions is limited.

Methods

In this retrospective, observational study, we investigated the key epidemiological characteristics, treatment patterns and responses among adult patients with newly diagnosed (ND) AML in China, who initiated treatment from January 1, 2015, to December 31, 2019, or progressed to relapsed/refractory (R/R) AML by December 31, 2020.

Results

Of the 853 ND AML patients included, 63.4% were screened for FLT3 status, and 20.1% tested positive (FLT3MUT) at initial diagnosis. Of 289 patients who progressed to R/R AML during the study period, 24.9% were screened at the diagnosis of R/R AML, and 19.4% tested positive; 20.5% of screened patients changed FLT3 status at first diagnosis of R/R AML. Initial treatment regimens or treatment responses did not seem to differ in patients with ND AML by FLT3 mutation status. In patients with R/R AML, there was an apparent difference in second-line treatment choices by FLT3 mutation status; however, the number of FLT3-mutated patients were limited to demonstrate any meaningful distinction. FLT3-mutated R/R AML was associated with shorter relapse time.

Conclusion

Study findings showed that there was a lack of routine testing for FLT3 mutations at first diagnosis of R/R AML, and initial treatment decisions did not differ by FLT3 mutation status. Given the clinical burden of FLT3MUT, likelihood of FLT3 status changes, and emerging FLT3 inhibitors, further routine FLT3 screening is needed to optimize treatment of R/R AML.

Healthcare resource utilization trends in patients with acute myeloid leukemia ineligible for intensive chemotherapy receiving first-line systemic treatment or best supportive care: A multicenter international study

Objectives

This retrospective chart review examined real‐world healthcare resource utilization (HRU) in patients with AML ineligible for intensive therapy who received first‐line systemic therapy or best supportive care (BSC).

Methods

Data were collected anonymously on patients with AML who initiated first‐line hypomethylating agents (HMA), low‐dose cytarabine (LDAC), other systemic therapy, or BSC. HRU endpoints included hospitalizations, outpatient consultations, transfusions, and supportive care.

Results

Of 1762 patients included, 46% received HMA, 11% received LDAC, 17% received other systemic therapy, 26% received BSC; median treatment durations were 118, 35, 33, and 57 days, respectively. Most patients were hospitalized, most commonly for treatment administration, transfusion, or infection (HMA 82%, LDAC 93%, other systemic therapy 83%, BSC 83%). A median number of hospitalizations were 2–6 across systemic groups and two for BSC, with median durations of 8–18 days. Transfusion rates and outpatient consultations were highest for HMA (80% and 79%) versus LDAC (57% and 53%), other systemic therapy (57% and 63%), and BSC (71% and 66%). Antivirals/antibiotics and antifungals were used more frequently than growth factors (72–92%, 34–63%, and 7–27%, respectively).

Conclusion

Patients with AML ineligible for intensive therapy have high HRU; novel therapies are needed to alleviate this burden.

Real-world treatment patterns and clinical outcomes in patients with AML in Japan who were ineligible for first-line intensive chemotherapy

Acute myeloid leukemia (AML) predominantly affects elderly adults, and its prognosis worsens with age. Treatment options for patients in Japan ineligible for intensive chemotherapy include cytarabine/aclarubicin ± granulocyte colony-stimulating factor (CA ± G), azacitidine (AZA), low-dose cytarabine (LDAC), targeted therapy, and best supportive care (BSC). The country's aging population and the evolving treatment landscape are contributing to a need to understand treatment pathways and associated outcomes. This retrospective chart review evaluated outcomes in patients across Japan with primary/secondary AML who were ineligible for intensive chemotherapy and began first-line treatment or BSC between 01/01/2015 and 12/31/2018. The primary endpoint was overall survival (OS); secondary endpoints included progression-free survival (PFS) and healthcare resource utilization (HRU). Of 199 patients (58% > 75 years), 121 received systemic therapy (38 CA ± G, 37 AZA, 7 LDAC, 39 other) and 78 received BSC. Median OS was 5.4, 9.2, 2.2, 3.8, and 2.2 months for CA ± G, AZA, LDAC, other systemic therapy, and BSC, respectively; median PFS was 3.4, 7.7, 1.6, 2.3, and 2.1 months, respectively. HRU rates were uniformly high, with > 80% patients hospitalized in each cohort. The poor clinical outcomes and high HRU among Japanese AML patients who are ineligible for intensive chemotherapy highlight an unmet need for novel therapies.

Real-world treatment patterns and clinical outcomes in patients with AML unfit for first-line intensive chemotherapy. Leuk Lymphoma 2022;63:928-938. [PMID: 35147482 DOI: 10.1080/10428194.2021.2002321]

Acute myeloid leukemia (AML) predominantly affects the elderly, and prognosis declines with age. Induction chemotherapy plus consolidation therapy is standard of care for fit patients; options for unfit patients include hypomethylating agents (HMA), low-dose cytarabine (LDAC), targeted therapies, and best supportive care (BSC). This retrospective chart review evaluated clinical outcomes in unfit patients with AML who initiated first-line treatment or BSC 01/01/2015-12/31/2018. Overall survival (OS), progression-free survival (PFS), time-to-treatment failure (TTF), and response rates were assessed. Of 1762 patients, 1310 received systemic therapies: 809 HMA, 199 LDAC, and 302 other therapies; 452 received BSC. Median OS was 9.9, 7.9, 5.4, and 2.5 months for HMA, LDAC, other, and BSC, respectively. Median PFS was 7.5, 5.3, 4.1, and 2.1 months for HMA, LDAC, other, and BSC, respectively; median TTF was 4.9, 2.1, 2.2, and 2.1 months, respectively. Our findings highlight the unmet need for novel therapies for unfit patients.

Cost-effectiveness of gilteritinib for relapsed/refractory FLT3mut+ acute myeloid leukemia

BACKGROUND: Patients with relapsed or refractory (R/R) acute myeloid leukemia (AML) and confirmed feline McDonough sarcoma (FMS)-like tyrosine kinase 3 gene mutations (FLT3^mut+) have a poor prognosis and limited effective treatment options. Gilteritinib is the first targeted therapy approved in the United States and Europe for R/R FLT3^mut+ AML with significantly improved efficacy compared with existing treatments. OBJECTIVE: To evaluate gilteritinib against salvage chemotherapy (SC) and best supportive care (BSC) over a lifetime horizon among adult patients with R/R FLT3^mut+ AML from a US third-party payer's perspective. METHODS: The model structure of this cost-effectiveness analysis included a decision tree to stratify patients based on their hematopoietic stem cell transplantation (HSCT) status, followed by 2 separate 3-state partitioned survival models to predict the long-term health status conditional on HSCT status. The ADMIRAL trial data and literature were used to predict probabilities of patients being in different health states until a conservative cure point at year 3. Afterwards, living patients followed the survival outcomes of long-term survivors with AML. Model inputs for utilities, medical resource use, and costs were based on the ADMIRAL trial, published literature, and public sources. All costs were inflated to 2019 US dollars (USD). Total incremental costs (in 2019 USD), life-years (LYs), quality-adjusted LYs (QALYs), and incremental cost-effectiveness ratios (ICERs) were calculated. Deterministic sensitivity analyses and probabilistic sensitivity analyses were performed. RESULTS: Over a lifetime horizon with a 3.0% annual discount rate, the base-case model estimated that gilteritinib led to an increase of 1.29 discounted QALYs at an additional cost of $148,106 vs SC, corresponding to an ICER of $115,192 per QALY; for BSC, results were an increase of 2.32 discounted QALYs, $249,674, and $107,435, respectively. The base-case findings were robust in sensitivity analyses. The estimated probabilities of gilteritinib being cost-effective vs SC and BSC were 90.5% and 99.8%, respectively, in the probabilistic sensitivity analyses, based on a willingness-to-pay threshold of $150,000 per QALY. CONCLUSIONS: Gilteritinib is a cost-effective novel treatment for patients with R/R FLT3^mut+ AML in the United States. DISCLOSURES: This work was supported by Astellas Pharma, Inc., which was involved in all stages of the research and manuscript development. Garnham, Pandya, and Shah are employees of Astellas and hold stock/stock options. Zeidan consulted and received personal fees/honoraria and research funding from Astellas. Zeidan also has received research funding from Celgene/BMS, Abbvie, Astex, Pfizer, Medimmune/AstraZeneca, Boehringer-Ingelheim, Trovagene/Cardiff Oncology, Incyte, Takeda, Novartis, Amgen, Aprea, and ADC Therapeutics; has participated in advisory boards; has consulted with and/or received honoraria from AbbVie, Otsuka, Pfizer, Celgene/BMS, Jazz, Incyte, Agios, Boehringer-Ingelheim, Novartis, Acceleron, Daiichi Sankyo, Taiho, Seattle Genetics, BeyondSpring, Cardiff Oncology, Takeda, Ionis, Amgen, Janssen, Syndax, Gilead, Kura, Aprea, Lox Oncology, Genentech, Servier, Jasper, Tyme, and Epizyme; has served on clinical trial committees for Novartis, Abbvie, Geron, Gilead, Kura, Lox Oncology, BioCryst, and Celgene/BMS; and has received travel support for meetings from Pfizer, Novartis, and Cardiff Oncology. Qi and Yang are employees of Analysis Group, Inc., which received consulting fees from Astellas for work on this study. Part of this material was presented at the American Society of Hematology (ASH) Annual Meeting; December 7-10, 2019; Orlando, FL.

A systematic literature review of disease burden and clinical efficacy for patients with relapsed or refractory acute myeloid leukemia

Acute myeloid leukemia (AML) is a rapidly progressive hematological malignancy that is difficult to cure. The prognosis is poor and treatment options are limited in case of relapse. A comprehensive assessment of current disease burden and the clinical efficacy of non-intensive therapies in this population are lacking. We conducted two systematic literature reviews (SLRs). The first SLR (disease burden) included observational studies reporting the incidence and economic and humanistic burden of relapsed/refractory (RR) AML. The second SLR (clinical efficacy) included clinical trials (phase II or later) reporting remission rates (complete remission [CR] or CR with incomplete hematologic recovery [CRi]) and median overall survival (mOS) in patients with RR AML or patients with de novo AML who are ineligible for intensive chemotherapy. For both SLRs, MEDLINE®/Embase® were searched from January 1, 2008 to January 31, 2020. Clinical trial registries were also searched for the clinical efficacy SLR. After screening, two independent reviewers determined the eligibility for inclusion in the SLRs based on full-text articles. The disease burden SLR identified 130 observational studies. The median cumulative incidence of relapse was 29.4% after stem cell transplant and 46.8% after induction chemotherapy. Total per-patient-per-month costs were $28,148-$29,322; costs and health care resource use were typically higher for RR versus non-RR patients. Patients with RR AML had worse health-related quality of life (HRQoL) scores than patients with de novo AML across multiple instruments, and lower health utility values versus other AML health states (i.e. newly diagnosed, remission, consolidation, and maintenance therapy). The clinical efficacy SLR identified 50 trials (66 total trial arms). CR/CRi rates and mOS have remained relatively stable and low over the last 2 decades. Across all arms, the median rate of CR/CRi was 18.3% and mOS was 6.2 months. In conclusion, a substantial proportion of patients with AML will develop RR AML, which is associated with significant humanistic and economic burden. Existing treatments offer limited efficacy, highlighting the need for more effective non-intensive treatment options.

Post-transplant maintenance therapy in patients with FLT3-mutated acute myeloid leukemia: Real-world treatment patterns and outcomes

Objectives

Maintenance therapy is one strategy to prolong survival in patients with acute myeloid leukemia (AML) following hematopoietic stem cell transplantation (HSCT). We evaluated real‐world treatment patterns and outcomes in patients with newly diagnosed FLT3‐mutated AML receiving HSCT after complete remission with first‐line chemotherapy.

Methods

A global, retrospective chart review to evaluate maintenance therapy and outcomes in patients with FLT3‐mutated AML after HSCT.

Results

Data from 1208 charts from eight countries showed that most patients (n = 765 [63.3%]) received no maintenance therapy after HSCT, 219 (18.1%) received FLT3 inhibitor maintenance therapy, and 224 (18.5%) received other types of maintenance therapy. No systematic differences were observed in healthcare resource utilization across the three groups. Clinical benefit was observed with FLT3 inhibitor maintenance over no maintenance therapy with relapse‐free survival (adjusted hazard ratio [HR] 0.57 [95% CI 0.34‐0.94], P < .05). FLT3 inhibitor and other maintenance also demonstrated overall survival benefit over no maintenance (adjusted HR 0.50 [95% CI 0.28‐0.89] and 0.46 [95% CI 0.23‐0.91], respectively; both P < .05).

Conclusions

Real‐world maintenance therapies after HSCT in patients with FLT3‐mutated AML were heterogeneous. While overall use of healthcare resources was not significantly increased in patients receiving maintenance therapy versus those who did not, clinical outcomes were improved.

Real-world treatment patterns and healthcare resource use in patients with acute myeloid leukemia in Western Europe

Aim: Assess treatment patterns and healthcare resource utilization (HRU) in patients with treatment-naive (TN) or relapsed/refractory (R/R) acute myeloid leukemia (AML) in Europe. Patients & methods: Cross-sectional, retrospective, web-based survey of AML-treating healthcare professionals (HCPs) in 12 European countries. Results: 320 HCPs provided information on 1280 TN or R/R patients. Patients ineligible versus eligible for intensive induction therapy required more general practitioner visits (4.1 vs 2.4), more uses of healthcare-related transport (6.9 vs 4.5), but less hospitalization (11.4 vs 27.5 days). Differences were observed in HRU and treatment patterns across countries. Conclusions: This analysis of 'real-world' patients with TN or R/R AML in Europe demonstrates substantial healthcare use, including higher use of resources in patients ineligible for intensive induction therapy.

A budget impact analysis of gilteritinib for the treatment of relapsed or refractory FLT3 mut+ acute myeloid leukemia in a US health plan

AIMS

To estimate the economic impact of the introduction of gilteritinib for the treatment of relapsed/refractory (R/R) FLT3 mutation-positive (FLT3 ^mut+) acute myeloid leukemia (AML) from a US payer's perspective.

METHODS

A budget impact model (BIM) was developed to evaluate the 3-year total budgetary impact of treating adults with R/R FLT3 ^mut+ AML eligible for gilteritinib in a hypothetical US health plan. Total costs (drugs/administration, hospitalization, monitoring, adverse events, transfusions, subsequent hematopoietic stem cell transplantation, post-progression, and FLT3 testing) were estimated before and after gilteritinib entry. The budget impact was the total cost difference between the two scenarios. The target population size and cost inputs were based on public data or published literature, drug market share was informed by market research data, and the model included recommended treatments for R/R FLT3 ^mut+ AML per clinical guidelines. Deterministic sensitivity analyses (DSAs) and scenario analyses varying key model inputs and assumptions were conducted to test for robustness.

RESULTS

In a hypothetical health plan with 1 million members, 20.9 adults with R/R FLT3 ^mut+ AML were estimated to be eligible for gilteritinib. Of these, it was assumed 30.0% would be treated with gilteritinib in Year 1 following gilteritinib entry, increasing the total plan budget by $663,795 and the per-member-per-month (PMPM) cost by $0.055. In Years 2-3, the market share of gilteritinib increased to 45.0%, increasing the total plan budget impact by $1,078,371 and $1,087,230, and the PMPM cost by $0.090 and $0.091, respectively. The model results remained robust in DSAs and scenario analyses, with the largest impact observed when the projected uptake of gilteritinib was changed.

LIMITATIONS

The results of this BIM are contingent upon the model's assumptions and inputs.

CONCLUSIONS

Adding gilteritinib to the formulary for the treatment of adults with R/R FLT3 ^mut+ AML had a minimal budget impact from a US payer's perspective.

Clinical and economic analysis of patients with acute myeloid leukemia by FLT3 status and midostaurin use at a Comprehensive Cancer Center

INTRODUCTION

Identification of cytogenetic and molecular abnormalities has become vital for the appropriate treatment of acute myeloid leukemia (AML). One of the most common molecular alterations in AML is the constitutive activation by internal tandem duplication of FMS-like tyrosine kinase 3 (FLT3).

METHODS

This observational, retrospective, cohort study at the Huntsman Cancer Institute (HCI) had two time periods: 1) a historical pre-midostaurin time period which consisted of the FLT3 mutated (FLT3m) and FLT3 wild type (FLT3wt) cohorts from January 1, 2007, to December 31, 2016, and 2) a post-midostaurin cohort which consisted of the FLT3 mutated midostaurin-user cohort (early mido) from May 01, 2017 to December 31, 2018.

RESULTS

In total, 39 patients were included in the FLT3m cohort, 61 in the FLT3wt cohort, and seven in the early mido cohort. FLT3m patients spent fewer days in the hospital during the first consolidation regimen and received fewer consolidation cycles compared to FLT3wt patients. Overall survival (OS) was similar between FLT3m and FLT3wt patients. For patients without hematopoietic stem cell transplant, OS was significantly shorter for FLT3m patients compared to FLT3wt patients. Mean AML related inpatient charges and physician charges for FLT3m patients were significantly higher than FLT3wt patients.

CONCLUSION

The FLT3 mutation is historically associated with a shorter time to transplant and increased total health care charges. More information is needed to evaluate the real-world treatment strategies for FLT3-mutated patients in the presence of FLT3 inhibitors and the impact of these treatment strategies on clinical and economic outcomes.

Treatment patterns and healthcare resource utilization in patients with FLT3-mutated and wild-type acute myeloid leukemia: A medical chart study

OBJECTIVES

To assess real-world treatment patterns and healthcare resource utilization (HRU) among patients with FLT3-mutated (FLT3mut ) and FLT3-wild-type (FLT3wt ) acute myeloid leukemia (AML).

METHODS

Data were abstracted from medical charts of patients with AML from 10 countries. Patients were grouped based on their FLT3 mutation status, age (18-64 or ≥65), and whether they were newly diagnosed (ND) or relapsed/refractory (R/R).

RESULTS

Charts of 1027 AML patients were included (183 FLT3mut 18-64 ND; 136 FLT3mut ≥65 ND; 181 FLT3mut R/R; 186 FLT3wt 18-64 ND; 159 FLT3wt ≥65 ND; 182 FLT3wt R/R). Substantial heterogeneity was observed in treatment patterns for AML. Among ND patients 18-64, the most common initial treatment was standard-to-intermediate dose cytarabine-based therapies (43.2% for FLT3mut and 55.9% for FLT3wt ); among ND patients ≥65, the most common initial treatment was hypomethylating agent-based therapies (36.0% and 47.2%). Among R/R patients, the most common initial treatment after R/R was best supportive care only (39.8% and 24.7%). HRU was substantial across cohorts during both event-free and post-event periods.

CONCLUSIONS

Treatment patterns of AML were heterogeneous and FLT3mut AML was treated more aggressively than FLT3wt disease. HRU was substantial for all cohorts, particularly after relapse or treatment failure.