LC-MRM-MS Quantitation of Co-administered Therapeutic Proteins
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for quantitating therapeutic proteins, especially when co-administered, face challenges due to interference from matrix components and competition, making it difficult to accurately and rapidly measure multiple therapeutic proteins of interest.
Innovation Solution
A liquid chromatography-multiple reaction monitoring mass spectrometry (LC-MRM-MS) approach combined with dual enzymatic digestion is developed to determine the total concentrations of each antibody component in an antibody cocktail, using unique surrogate peptides generated by trypsin and AspN digestion, which are then quantitated using a mass spectrometer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If ligand binding assays (LBAs) are used for quantitation of therapeutic proteins, then measurement accuracy can be achieved, but the method development process is slow and complex
Solution Approach 1:
The patent replaces the mechanical/chemical binding mechanism of LBAs with a mass spectrometry-based detection system. LC-MS/MS uses mass-to-charge ratio detection instead of ligand binding, enabling faster method development while maintaining quantitation accuracy through direct molecular identification of surrogate peptides.
Solution Approach 2:
The patent uses surrogate peptides as simplified copies of the full therapeutic protein. These peptides contain unique sequences that represent the protein of interest, allowing MS detection to quantify the full protein without requiring complex antibody-based ligand binding systems.
2Measurement precision
If LC-MS/MS is used to analyze a single therapeutic protein, then quantitation can be achieved, but co-administered therapeutic proteins cause interference and competition making quantitation difficult
Solution Approach 1:
The patent segments the analysis by selecting unique surrogate peptides specific to each therapeutic protein in the cocktail. Each antibody is represented by its own unique peptide sequence, allowing the MS system to distinguish and quantify each component separately despite their presence in the same sample matrix.
Solution Approach 2:
The patent applies local quality by making each surrogate peptide unique to its parent therapeutic protein. The surrogate peptides have distinct mass-to-charge ratios and fragmentation patterns, enabling selective detection and quantitation of each antibody component without interference from other co-administered proteins.
3Reliability
If multiple therapeutic proteins are co-administered, then therapeutic efficacy is improved, but identification and quantitation of individual proteins becomes difficult
Solution Approach 1:
The patent uses surrogate peptides as intermediary markers for each therapeutic protein. These peptides serve as mediators that link the presence of the full protein to detectable MS signals, enabling indirect but accurate quantitation of each antibody component in the cocktail through their unique peptide representatives.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method provides accurate, rapid, and simultaneous quantitation of multiple co-administered therapeutic proteins, with a dynamic range of 10 to 2000 μg/mL, and demonstrates comparable pharmacokinetic profiles to fully validated electrochemiluminescence immunoassays, offering a faster and more efficient alternative to traditional ligand-binding assays.
Implementation Method 1
LC-MS/MS offers a number of advantages that provide for a much faster method development process. A key aspect of using LC-MS/MS to analyze a therapeutic protein is through quantitation of a surrogate peptide, derived from proteolytic digestion, as a unique identifier of the protein.
Implementation Method 2
generating a unique surrogate peptide for each of said first and second therapeutic proteins by contacting said sample to at least two digestive enzymes
Implementation Method 3
Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) is becoming a preferred method for analysis of biopharmaceuticals
Implementation Method 4
said mass spectrometer is an electrospray ionization mass spectrometer, nano-electrospray ionization mass spectrometer, or a triple quadrupole mass spectrometer
Data Source
AI summary
The present invention generally pertains to methods of quantitating therapeutic proteins co-administered to a subject using LC-MRM-MS. In particular, the present invention pertains to the use of dual enzymatic digestion to generate unique surrogate peptides allowing for the accurate quantitation of co-administered therapeutic proteins using LC-MRM-MS.