A validated LC-MS/MS method for the quantitation of daratumumab in rat serum using rapid tryptic digestion without IgG purification and reduction

J Pharm Biomed Anal. 2024 Jun 15:243:116083. doi: 10.1016/j.jpba.2024.116083. Epub 2024 Mar 2.

Abstract

Daratumumab, a humanized monoclonal antibody utilized in treating immunoglobulin light-chain amyloidosis and relapsed/refractory multiple myeloma, was quantified in rat serum through a simple, economical and effective liquid chromatography tandem-mass spectrometry (LC-MS/MS) method. A surrogate peptide, LLIYDASNR, derived from trypsin hydrolysis, was quantitatively analyzed with LLIYDASN [13C6, 15N4] RAT as an internal standard. This corrected variations from sample pretreatment and mass spectrometry response, involving denaturation and trypsin hydrolysis in a two-step process lasting approximately 1 hour. Methodological validation demonstrated a linear range of 1 µg/mL to 1000 µg/mL in rat serum. Precision, accuracy, matrix effect, sensitivity, stability, selectivity, carryover, and interference met acceptance criteria. The validated LC-MS/MS approach was successfully applied to a pharmacokinetic study of daratumumab in rats at an intravenous dose of 15 mg/kg.

Keywords: Daratumumab; LC-MS/MS; Pharmacokinetics; Surrogate peptide.

MeSH terms

  • Antibodies, Monoclonal / chemistry
  • Chromatography, Liquid / methods
  • Digestion
  • Immunoglobulin G
  • Liquid Chromatography-Mass Spectrometry*
  • Reproducibility of Results
  • Tandem Mass Spectrometry* / methods
  • Trypsin

Substances

  • daratumumab
  • Trypsin
  • Antibodies, Monoclonal
  • Immunoglobulin G