Initial Experience With CMC-544 (Inotuzumab Ozogamicin) in Pediatric Patients With Relapsed B-cell Acute Lymphoblastic Leukemia

Pediatr Blood Cancer. 2014 Feb;61(2):369-72. doi: 10.1002/pbc.24721. Epub 2013 Sep 2.

Abstract

Survival is poor in pediatric patients with relapsed or refractory acute B-cell lymphoblastic leukemia (ALL) and therapeutic options are limited. CMC-544 (inotuzumab ozogamicin) has shown significant activity in adult patients with relapsed and refractory ALL. We evaluated CMC-544 in pediatric patients with multiply relapsed ALL. Five children 4-15 years old with relapsed, CD 22 positive B-cell ALL were enrolled on a phase II non-randomized trial of CMC-544. CMC-544 was initially administered at 1.3 mg/m(2) every 3 weeks. The dose then increased to 1.8 mg/m(2) every 3 weeks. Subsequently, a weekly schedule of CMC-544 given as 0.8 mg/m(2) on day 1 followed by 0.5 mg/m(2) on days 8 and 15 was administered. All five patients had refractory relapsed B-cell ALL. Lymphoblasts for all patients highly expressed CD22. Four patients had two or more relapses before starting the study drug. One patient achieved a complete remission in the bone marrow and normal peripheral counts, and two patients achieved bone marrow morphologic remission with absolute neutrophils >1,000/µl but platelets <100,000/µl. Two patients had no response to the drug. Toxicities consisted of fever, sepsis, and liver enzyme elevation. Single agent CMC-544 given at the single dose of 1.8 mg/m(2) every 3 weeks or given as a split, weekly dose was generally well tolerated considering the inherent risks in this population of patients and showed promising activity in pediatric patients with relapsed and refractory ALL.

Keywords: CD 22; CMC-544; acute lymphoblastic leukemia; relapse.

MeSH terms

  • Adolescent
  • Adult
  • Antibodies, Monoclonal, Humanized / therapeutic use*
  • Child
  • Child, Preschool
  • Female
  • Follow-Up Studies
  • Humans
  • Inotuzumab Ozogamicin
  • Lymphoma, B-Cell / drug therapy*
  • Lymphoma, B-Cell / pathology
  • Male
  • Neoplasm Recurrence, Local / drug therapy*
  • Neoplasm Recurrence, Local / pathology
  • Neoplasm Staging
  • Precursor Cell Lymphoblastic Leukemia-Lymphoma / drug therapy*
  • Precursor Cell Lymphoblastic Leukemia-Lymphoma / pathology
  • Prognosis
  • Remission Induction
  • Retrospective Studies
  • Salvage Therapy*

Substances

  • Antibodies, Monoclonal, Humanized
  • Inotuzumab Ozogamicin