Minimal residual hairy cell leukemia eradication with moxetumomab pasudotox: Phase 1 results and long-term follow-up Academic Article uri icon


MeSH Major

  • Precursor Cell Lymphoblastic Leukemia-Lymphoma


  • Copyright 2011 by The American Society of Hematology. Anti-CD22 moxetumomab pasudotox achieved 46% complete remissions (CRs) in previously reported phase 1 testing in relapsed/refractory hairy cell leukemia (HCL; n 5 28). The importance of minimal residual disease (MRD) after CR in HCL is unknown. A 21-patient extension cohort received 50 mg/kg every other day for 3 doses in 4-week cycles. These patients plus 12 previously reported at this upper dose level received 143 cycles without dose-limiting toxicity. The combined 33-patient cohort achieved 64% CR and 88% overall response rates, with median CR duration of 42.4 months. Of 32 50-mg/kg patients evalua ble for MRD by bone marrow aspirate flow cytometry (most stringent assessment), median CR duration was 13.5 (4.9-42.4) months in 9 MRD-positive CRs vs 42.1 (24.0-69.2) months in 11 MRD-negative CRs (P < .001). Among MRD-negative CRs, 10 patients had ongoing CR, 9 without MRD, at end of study. To our knowledge, moxetumomab pasudotox is the only nonchemotherapy regimen that can eliminate MRD in a significant percentage of HCL patients, to enhance CR duration. Repeated dosing, despite early neutralizing antibodies, increased active drug levels without detectable toxicity from immunogenicity. The activity and safety profiles of moxetumomab pasudotox support ongoing phase 3 testing in HCL.

publication date

  • May 24, 2018



  • Academic Article



  • eng

Digital Object Identifier (DOI)

  • 10.1182/blood-2017-09-803072

PubMed ID

  • 29487070

Additional Document Info

start page

  • 2331

end page

  • 2334


  • 131


  • 21