HCP Assay Development

Charles River's HCP-GAPex℠ service is the first holistic approach to host cell protein assay development. Combining tools from proteomics, bioinformatics, protein synthesis, and immunology, the service minimizes black box elements, provides targeted enhancement of coverage, and maximizes the performance of HCP assays. The assays used accurately monitor changes in the product concentration and the removal of host cell proteins after purification. 

Early Phase HCP Assays

In the early process development phase as well as in early clinical phases, generic HCP assays are normally acceptable. Charles River supports these phases with:

  • Qualification of commercially available kits 
  • CGMP-compliant testing of clinical trial material using commercially available kits 
  • Identification and quantitation of HCPs in samples from process development and drug manufacturing using mass spectrometry

Clinical Phase III HCP Assays

Once a biopharmaceutical is used in clinical Phase III studies, a validated, product-specific HCP assay is normally required. We are experts in the field of customized HCP assay development and offer a fully integrated approach for this, including:

  • Development of customized assays on different expression systems using either ELISA or ILA 
  • Inoculation of antigens for antiserum production and then purification of antibodies for use in client-specific assays
  • Antibody generation, purification, characterization, and labeling for use in client-specific assays 
  • GMP-compliant validation of assays and routine testing services 
  • Lifecycle management of assay reagents, including long-term storage 

 HCP: New Tools For An Ongoing Challenge

Image of antibody. The complexity and heterogeneity of host cell proteins always requires a polyclonal antiserum for assay development.

In this webinar you will learn more about HCP testing regulations, the risks of using a non-appropriate HCP method, and different assay approaches that are available.

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We offer best-in-class service for host cell proteins immunoassays and mass spectrometry under one roof. Leveraging both technologies, we are able to generate a near-perfect HCP assay by applying the HCP-GAPex℠ strategy.

Consult An Expert

Frequently Asked Questions (FAQs) about Host Cell Proteins

  • What are host cell proteins?

    Host cell proteins (HCPs) are an inevitable impurity of biopharmaceuticals, regardless of whether they are produced by recombinant fermentation or extracted from natural sources. Even after multiple sophisticated purification steps, HCPs may remain or co-purify. They represent a heterogeneous variety of different proteins that need to be quantified in the drug substance and in intermediates from the downstream purification process. 

  • How are host cell proteins calculated?

    Typically for HCP analysis, the HCP content is calculated as a concentration (ng/mL) and/or as the HCP load per therapeutic dose.  

  • What is HCP analysis?

    HCP analysis is a test to determine the concentration of host cell proteins in samples from downstream purification and drug substance. 

  • What is the host cell protein assay development process?

    The process of a holistic approach for HCP assay development starts with the definition/selection of a suitable antigen that can be characterized and conditioned before it gets injected into rabbits, goats, or chickens. Over the time course of the immunization, the animals are thoroughly checked for titer and the specific immune response. The specific anti-HCP antibodies are purified from the antisera and characterized by 2D gel/Western blot for the linear coverage and ideally by pull-down affinity experiments and mass spectrometry readout. The characterized antibody pool is used for the setup and optimization of the immunoassay, which can be validated and used in routine lot release testing.