Midostaurin in combination with chemotherapy is most effective in patients with acute myeloid leukemia presenting with high FLT3-ITD allelic ratio who proceed to allogeneic stem cell transplantation while in first complete remission

Eur J Haematol. 2021 Jan;106(1):64-71. doi: 10.1111/ejh.13518. Epub 2020 Oct 6.

Abstract

Objectives: Midostaurin, a multikinase and FLT3 inhibitor, is the first non-chemotherapy agent approved and widely adopted for the treatment of FLT3-ITD acute myeloid leukemia (AML). Yet, its role in improving survival of patients referred to allogeneic stem cell transplantation (allo-SCT) in first complete remission (CR1) needs to be defined.

Methods: This multicenter study retrospectively evaluated the outcome of 119 FLT3-ITD AML patients [59 (49.6%) males and 60 females] intensively treated between 2015 and 2019 at five Israeli centers. In our cohort, allo-SCT in CR1 was widely implemented (47%) and patient stratification was based on the current allelic ratio (AR) cutoff of 0.5.

Results: Ninety-eight patients (82.3%) achieved CR1/CR with incomplete count recovery (CRi). Death during induction was reported in 7 (5.9%) patients. In multivariate analysis, midostaurin use and allo-SCT in CR1 were the most significant factors affecting overall survival (OS). Midostaurin incorporation in chemotherapy regimens significantly improved CR + CRi rates (P = .002), reduced relapse rates (P = .02), and was remarkably advantageous for high-AR patients (2-year OS 82%). In low-AR patients, the midostaurin effect was much less prominent.

Conclusions: Our results demonstrate benefits of midostaurin incorporation in intensive chemotherapy regimens, particularly for high-AR AML patients to whom it should be offered along with allo-SCT in CR1.

Keywords: acute myeloid leukemia; allogeneic stem cell transplantation; fms-like tyrosine kinase 3-internal tandem duplication; midostaurin.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Antineoplastic Combined Chemotherapy Protocols / adverse effects
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use*
  • Combined Modality Therapy
  • Female
  • Gene Duplication*
  • Gene Frequency*
  • Hematopoietic Stem Cell Transplantation* / methods
  • Humans
  • Leukemia, Myeloid, Acute / diagnosis
  • Leukemia, Myeloid, Acute / genetics*
  • Leukemia, Myeloid, Acute / mortality
  • Leukemia, Myeloid, Acute / therapy*
  • Male
  • Middle Aged
  • Prognosis
  • Remission Induction
  • Retrospective Studies
  • Staurosporine / administration & dosage
  • Staurosporine / analogs & derivatives
  • Transplantation, Homologous
  • Treatment Outcome
  • fms-Like Tyrosine Kinase 3 / genetics*

Substances

  • FLT3 protein, human
  • fms-Like Tyrosine Kinase 3
  • Staurosporine
  • midostaurin