A phase 1 trial of vadastuximab talirine as monotherapy in patients with CD33-positive acute myeloid leukemia.

Published

Journal Article

Vadastuximab talirine (SGN-CD33A, 33A) is an antibody-drug conjugate consisting of pyrrolobenzodiazepine dimers linked to a monoclonal antibody targeting CD33, which is expressed in the majority of acute myeloid leukemia (AML) patients. This phase 1 study evaluated the safety, pharmacokinetics, and preliminary activity of vadastuximab talirine and determined the recommended monotherapy dose in patients with relapsed or refractory AML. Additional expansion cohorts tested vadastuximab talirine in specific subpopulations of relapsed AML, and in a cohort of older, treatment-naive patients. Patients received vadastuximab talirine IV on day 1 (5-60 µg/kg) or on days 1 and 4 (20 µg/kg) of 21-day cycles. A total of 131 patients (median age, 73 years [range, 26-89 years]) had intermediate I-II (48%) or adverse (34%) risk by European LeukemiaNet classification; 50% of patients had underlying myelodysplasia. Two dose-limiting toxicities (grade 2 pulmonary embolism and grade 4 hypocellular marrow) occurred during dose finding. Most adverse events (AEs) were consistent with myelosuppression; nonhematologic AEs included fatigue, nausea, and diarrhea. The 30-day mortality was 8%. At the recommended monotherapy dose of 40 µg/kg, the complete remission + CRi rate was 28% (5 of 18 patients); 50% of patients who responded achieved minimal residual disease negativity. In patients across dose levels who achieved CR or CRi, the median time to full count recovery was 6.4 weeks for neutrophils (≥1000/µL) and 10.6 weeks for platelets (≥100 × 109/L). Vadastuximab talirine demonstrates activity and a tolerable safety profile as a single agent in patients with AML. The recommended monotherapy dose of vadastuximab talirine is 40 µg/kg. This trial was registered at www.clinicaltrials.gov as # NCT01902329.

Full Text

Duke Authors

Cited Authors

  • Stein, EM; Walter, RB; Erba, HP; Fathi, AT; Advani, AS; Lancet, JE; Ravandi, F; Kovacsovics, T; DeAngelo, DJ; Bixby, D; Faderl, S; Jillella, AP; Ho, PA; O'Meara, MM; Zhao, B; Biddle-Snead, C; Stein, AS

Published Date

  • January 25, 2018

Published In

Volume / Issue

  • 131 / 4

Start / End Page

  • 387 - 396

PubMed ID

  • 29196412

Pubmed Central ID

  • 29196412

Electronic International Standard Serial Number (EISSN)

  • 1528-0020

Digital Object Identifier (DOI)

  • 10.1182/blood-2017-06-789800

Language

  • eng

Conference Location

  • United States