Accurate and reliable real-time protein titer monitoring in biopharma

By Maxwell Geiger, Associate Product Solutions Manager for the BioProcess Analytics group within IDEX Health & Science

Recently, regulators have encouraged pharma and biopharma companies to incorporate the concepts of Quality by Design (QbD) and Process Analytical Technology (PAT) into drug development and manufacturing processes (1). This encouragement is part of a drive for scientists to gain as much knowledge about a new drug as possible and on using a considered set of Critical Process Parameters (CPPs) to subsequently control production.

However, to date, few drugs have been filed based on QbD data and experts have suggested that the nature of biologics leads to complex quality concerns and a significantly higher number of input parameters that can have an impact on product quality. As a result, the implementation of QbD within biopharma calls for a significant level of detailed information gathering.

Analytical testing of cell culture in monoclonal antibody (mAb) production calls for quick, robust antibody titer measurements with a wide dynamic range, to monitor product yields throughout a bioreactor run and downstream processes. Identifying a parameter as important, such as IgG titer, creates a requirement for reliable detection.

There is a need within the industry for an analytical instrument that can deliver the essential insights into such complex quality concerns in a way that provides consistency of methodology as a process moves from research to production.

Impact of Real-Time Protein Monitoring

Commonly considered essential for characterizing upstream bioprocessing efficiency, titer measurements indicate the proportion of product relative to nutrients and by-products for a given bioreactor volume. In addition to a wide dynamic range and robustness, accuracy, speed, and specificity are key features in titer measurement systems.

The accurate and reliable measurement of protein titer is essential for ensuring optimal cell culture performance to produce biologics. The ability to reliably monitor protein titer in real time throughout a bioprocess allows operators to rapidly adjust the process conditions for maximum protein output while minimizing the process time. Quick access to titer data also enables earlier decisions regarding preparation of downstream purification systems (e.g., protein A), further reducing the production timeline. Currently it is common for manufacturing teams to wait 24 hours or more to receive the offline titer data necessary to begin downstream purification resulting in an expensive bottleneck.

Furthermore, real-time monitoring of protein titer facilitates the adoption of continuous bioprocessing. This capability can enable process feedback control based on actual product concentration.

New Purpose-Built Solution

Recent work has compared a novel protein analyzer (Tridex Protein Analyzer, IDEX Heath & Science) with current methods to highlight how the analyzer uses a trap-and-elute technology to obtain rapid at-line measurement of antibody titers from stirred bioreactors. The unique trap-and-elute technique, which quantifies the amount of IgG in a cell-free sample, delivers accurate titer measurements over a dynamic range of 0.1–10 g/L with minimal sample manipulation. The sample flowpath is completely enclosed, lending itself to the requirements of single use. As a result, the Tridex Protein Analyzer offers a solution for at-line titer monitoring in a bioprocess environment that provides actionable data quickly, enabling critical decisions to be made in real time.

Performance Comparable to HPLC

High-performance liquid chromatography (HPLC) is the current standard technique for determining titer. Although a powerful technique, HPLC requires a high level of skill and expertise to operate and as a result, HPLC capability is rarely accessible at-line, making measurements at multiple stages of the bioprocess challenging. The performance of the Tridex Protein Analyzer has been shown to provide at-line results that directly correlate to offline HPLC methodology. In-house (2) and field testing (3-5) have shown that the system provides results within +10% of those obtained using offline HPLC over the full measurement range. In one example, excellent intra-assay precision (CV < 3%) was demonstrated for both at-line and on-line measurements obtained with the Tridex Analyzer and a commercial Protein A HPLC system (2). Measurement data were also shown to be unaffected by changing BSA levels up to 2.5% (v/v).

Conclusion

As the need for faster drug development intensifies the standards of identifying and measuring specific parameters that indicate scientific understanding of process and product quality are becoming essential. The development of novel systems that provide this practical utility, such as the Tridex Protein Analyzer indicate a clear way forward. Real-time titer measurements can provide valuable insights for cell line development and process development optimization, and the protein analyzer could become an invaluable tool for measuring CPPs in real time during the manufacture of antibodies.

For more information on the Tridex Protein Analyzer, please visit idex-hs.com/bioprocessing/protein-analyzer/.

References

1. Guidance for Industry PAT – A Framework for Innovative Pharmaceutical Development, Manufacturing, and Quality Assurance, Food and Drug Administration (FDA), 2004.
2. Bravo, J.; Love, C.; Yuan, C. Automating Titer Measurement, 2019. IDEX Health & Science. idex-hs.com/bioprocessing/protein-analyzer/literature/ (accessed May 13, 2020).
3. Karim, S.; Pagila, R.; Patel, N.; Quach, S.; Rose, V. A Novel Approach to Real Time Monitoring of Antibody Titer in a Fed-Batch Bioreactor Run, 2018. idex-hs.com/bioprocessing/protein-analyzer/literature/ (accessed May 13, 2020).
4. Karim, S.; Myles, T.; Pagila, R.; Patel, N.; Quach, D. Comparing Bioreactor Antibody Titer Measurements Obtained in Real Time to Other Antibody Measuring Techniques, 2018. idex-hs.com/bioprocessing/protein-analyzer/literature/ (accessed May 13, 2020).
5. Kottayil, N.; Love, C.; Pagila, R.; Patel, N.; Novel Device Enables Direct Measurement of Antibody Titers Up to 10 g/L in Real Time Without Sample Manipulations, 2019. idex-hs.com/bioprocessing/protein-analyzer/literature/ (accessed May 13, 2020).

About the author

Maxwell Geiger has been a product manager with IDEX Health & Science BioProcess Analytics for 3 years. A chemist by training, he brings diverse experience in chromatography and mass spectroscopy and thin films to the BioProcess Analytics team.

For more information, visit: idex-hs.com.