Clinical implications of pathophysiological and demographic covariates on the population pharmacokinetics of trastuzumab emtansine, a HER2-targeted antibody-drug conjugate, in patients with HER2-positive metastatic breast cancer

J Clin Pharmacol. 2012 May;52(5):691-703. doi: 10.1177/0091270011403742. Epub 2011 Sep 27.

Abstract

Trastuzumab emtansine (T-DM1) is a HER2-targeted antibody-drug conjugate in development for treatment of HER2-positive cancers. T-DM1 has been tested as a single agent in a phase I and 2 phase II studies of patients with heavily pretreated metastatic breast cancer (MBC), with the maximum tolerated dose established at 3.6 mg/kg intravenously for every-3-week dosing. The authors present results from the population pharmacokinetics analysis for T-DM1. Population pharmacokinetics for T-DM1 were characterized using a clinical database of 273 patients from the 3 studies. Pharmacokinetics was best described by a linear 2-compartment model. Population estimates (interindividual variability [IIV]) for pharmacokinetic parameters were clearance, 0.7 L/d (21.0%); central compartment volume (V(c)), 3.33 L (13.2%); peripheral compartment volume (V(p)), 0.89 L (50.4%); and intercompartmental clearance, 0.78 L/d. Body weight, albumin, tumor burden, and aspartate aminotransferase levels were identified as statistically significant covariates accounting for interindividual variability in T-DM1 pharmacokinetics, with body weight having a greater effect on IIV of clearance and V(c) than other covariates. T-DM1 exposure was relatively consistent across the weight range following body weight-based dosing. This analysis suggests no further T-DM1 dose adjustments are necessary in heavily pretreated patients with MBC.

Publication types

  • Clinical Trial, Phase I
  • Clinical Trial, Phase II
  • Multicenter Study

MeSH terms

  • Ado-Trastuzumab Emtansine
  • Adult
  • Antibodies, Monoclonal, Humanized / administration & dosage
  • Antibodies, Monoclonal, Humanized / adverse effects
  • Antibodies, Monoclonal, Humanized / pharmacokinetics*
  • Aspartate Aminotransferases / blood
  • Biomarkers, Tumor / immunology
  • Biomarkers, Tumor / metabolism*
  • Body Weight
  • Breast Neoplasms / blood
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / immunology
  • Breast Neoplasms / pathology
  • Drug Administration Schedule
  • Drug Dosage Calculations
  • Female
  • Humans
  • Immunotoxins / administration & dosage
  • Immunotoxins / adverse effects
  • Immunotoxins / pharmacokinetics*
  • Infusions, Intravenous
  • Linear Models
  • Maximum Tolerated Dose
  • Maytansine / administration & dosage
  • Maytansine / adverse effects
  • Maytansine / analogs & derivatives*
  • Maytansine / pharmacokinetics
  • Middle Aged
  • Models, Biological
  • Protein Binding
  • Receptor, ErbB-2 / immunology
  • Receptor, ErbB-2 / metabolism*
  • Serum Albumin / metabolism
  • Trastuzumab
  • Treatment Outcome
  • Tubulin Modulators / administration & dosage
  • Tubulin Modulators / adverse effects
  • Tubulin Modulators / pharmacokinetics*
  • Tumor Burden

Substances

  • Antibodies, Monoclonal, Humanized
  • Biomarkers, Tumor
  • Immunotoxins
  • Serum Albumin
  • Tubulin Modulators
  • Maytansine
  • Aspartate Aminotransferases
  • ERBB2 protein, human
  • Receptor, ErbB-2
  • Trastuzumab
  • Ado-Trastuzumab Emtansine