Biologics require specialised analytics assays to rigorously assess potency, infectivity and genome titer. Optimising these assays can provide insights that speed up development and approval.
Bioanalytics are key to accurate quantifications of any clinical product as part of a pharmacokinetic assessment. For biologics and gene therapies, this typically means measuring expression of an exogenous protein or gene. Immunological reactions to gene therapies also need to be integrated into analytics and dose-selection processes.
Both in vitro and in vivo studies play a critical role in bioanalysis of CGT products. USFDA guidance requires that CGT products have a robust in vitro potency assays to assess safety and efficacy. Absorption Systems has worked with regulators to develop assays that overcome the challenges associated with these studies, including:
- complex and / or unclear mechanisms of action
- complicated manufacturing processes
- variable critical quality attributes (CQAs)
- reduced preclinical and early stage clinical data with which to inform development
To learn more about in vitro potency assays for CGT products, download the inaugural version of the potency assay guide.
The Absorption Systems Difference
Absorption Systems was established with the mission of improving human outcomes by providing predictive research tools to the pharmaceutical industry. For over 20 years we have been developing well-controlled, biologically relevant test systems and validating them to support FDA approvals. Our experience includes creating and characterizing custom engineered cell lines to silence or overexpress target genes. As a CGT partner, ACF Bioservices and Absorption Systems offer expertise and resources to leverage our scientific knowledge to improve: productivity, efficiency, insight and experience, compliance and governance. These cumulative advantages reduce assay development time and risk, easing the submission process for approval of CGT products.
FREQUENTLY ASKED QUESTIONS
Analytical Tools and Techniques
- Quantitative Western Blot
- Enzyme Activity Assays
- ELISpot and FluoroSpot
- Luminex Multiplex Technology
- PCR, qPCR, and ddPCR
TECHNOLOGIES AND CAPABILITIES
What types of ELISA assay can Absorption Systems perform?
We have decades of experience conducting ELISA experiments for a wide range of applications. We always look to choose the most suitable protocol for the question at hand, these include the follow ELISA formats:
In the context of biologic analytical assays, these ELISA systems can be used to:
- validate the commercial kits, assay transfer or develop the test from the scratch (LDT).
- perform Assay Qualification, RUO Validation, and GxP Validation
- antigen-antibodies interaction studies
- large molecules and protein PK studies
- ADA, TAb, NAb detection
How are quantitative western blots used in biologic analytics?
Western blot analysis is an immunological testing method that can detect a protein of interest from a mixture of a great number of proteins. Western blotting generates information about the size of a protein and how that protein is expressed when compared directly to a control sample. Samples for analysis can include cells, tissues, and synthesized recombinant proteins. The success of the western blot method depends upon the quality and specificity of the antibodies used to detect a response against a specific protein of interest.
Absorption Systems can generate a method for a western blot utilized in either R&D applications or in a GLP/cGMP study. There is an additional charge for GLP and cGMP methods as compared to R&D projects. Using the Syngene System, western blots can be quantitated through the GeneSnap Software and particular methods can be validated for use in clinical trials.
How can ELISPOT and Fluorspot assays be used in biologic analytics?
- Assays in 96-well plates allow rapid analysis of large numbers of samples
- Quantification of the number of cytokine (for example IFN-γ or TNF-α) secreting cells.
- The ELISPOT assay can be used to determine effects of drugs or other compounds on cytokine secretion in vitro.
- Monocytes/macrophages/dendritic cells characterization
- Apolipoproteins analysis
- The ELISPOT assay can be used to determine the frequency of antigen-specific cytotoxic T cells (CTL) in fresh unstimulated peripheral blood.
How can immounological responses be quantified?
Absorption Systems have a range of different assays for assessing the immunological response to biologic therapies. A key technology in our portfolio is Luminex. Luminex is based on the principles of Flow Cytometry, and uses a single 5.6 micron size microspehere that are dyed with red and infrared dyes in different combinations to create 500 uniquely colored microspheres. Applications for Luminex include:
- bead array assays for rapid biomarker quantification
- assessment of serological immunity after successful vaccination
- assessment of immunogenicity
- cytokines, chemokines and growth factors
- cell signaling pathways
- adverse effect diagnosis, for example, cytokine storm, by comparing a baseline samples to various time points after administration of vaccines
- fluorescent/Luminescent Assay
We have both ready to use kits from Vendors (Affymetrix, Millipore, Bio-Rad etc) or use in-house developed kits.
How can PCR-based assays supprot biologic analytics?
As many biologic products involve viral expression of a gene product or gene knockout machinery, PCR of viral DNA and genes-of-interest can be extremely informative. We have a range of PCR, qPCR and ddPCR based assays that can be used to assess:
- Transduction/Transfection efficiency
- Retroviral vector-based gene therapy products testing
- Analysis of patient PBMC for RCR-specific DNA sequences
- Determination of efficacy of drugs on target genes
- Analysis of the spread of diseases virus, bacterial, parasites
- Viral Shedding
- Gene Expression
- Mutation Detection
- Genetic Variation
Where do in vitro potency assays sit in the regulatory approval process for CGT products?
Potency assays are used in both pre- and post-approval activities of CGT products. During development, potency assays are a key metric for assessing different formulations, delivery vectors, genome titre.
Once approved, potency assays are required to test each lot of CGT product prior to use. As stated by USFDA guidance, ““No lot of any licensed product shall be released by the manufacturer prior to the completion of tests for conformity with standards applicable to such product,” (21 CFR 610.1). These tests include potency, sterility, purity, and identity assays.