BioPhorum’s survey into ready-to-use cells in bioassays – the results are in!

1 March 2024
Development Group
Elaine Stokes
Senior Global Change Facilitator

Bioassays are a crucial part of an analytical control strategy for biopharmaceuticals. The adoption of ‘ready-to-use’ (RtU) cells in a GMP potency assay, can increase operational flexibility and improve assay reliability by providing frozen cell banks that are uniform in composition, while removing the challenges and cost around maintaining cultured cells.

To provide alignment on the terminology, production, qualification, and implementation of RtU cells to support the potency assay lifecycle, the BioPhorum Development Group Bioassay workstream conducted a benchmarking survey and held group discussions around the use of RtU cells for bioassays.

The results have now been published in An industry perspective approach and control strategy for implementation of ready-to-use cells in bioassays: survey outcome and recommendations.

“This is a first-of-its-kind compilation and establishment of standard best practices shared by subject matter experts across the biologics industry for producing, implementing, and handling RtU cells for QC cell-based potency assays,” said Isam Qahwash, Associate Director, Bioassay Center of Excellence at BMS.

Published in the BioTechniques Journal, the article outlines common industry practices used to establish, control, and use RtU cells in potency assays from concept through to commercialization. It discusses a range of issues, such as the considerations for implementing RtU cells in bioassays, the generation and logistics of RtU cell banks, release strategies (including assay performance), and the lifecycle management of RtU cell banks for analytical testing.

Eva Martinez, Head of Biological Method Development & In-process Sampling and Analytics (BMD & IPSA) at UCB said the article collected the approaches that organizations across the industry use for RtU cell generation and management. “It will promote the use of RtU cells and give guidance to the laboratories that want to start working with them.”

We found a number of common practices for the use of RtU cells, including introducing RtU cells as early as possible to gain maximum experience with making and using the cells before validation. Another key finding was the concept of using a two-tiered cell banking system for the manufacturing of RtU cells, where RtU cell banks would be derived from a similar master cell bank/working cell bank model.

John White, Director of Bioassay Development at GSK, said, “The paper will give insight to regulatory agencies as to the strategy that industrial leaders are using to implement and manage RtU cell.”

Want to know more?

To share the results of the survey and give you the opportunity to discuss the findings, we are hosting a free webinar on 19 March. You can register for this event here.

For more information, download the article here and contact Elaine Stokes, Senior Global Change Facilitator, at

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