2026_Contact_Envelope

USP Releases New General Chapter <89.3>: Advancing Endonuclease Standardization in Biopharmaceutical Manufacturing

Author /

The United States Pharmacopeia (USP) has released General Chapter <89.3> Endonuclease (Serratia marcescens), introducing a harmonized framework for measuring endonuclease activity. This marks an important step toward greater standardization for a critical ancillary material used in modern biopharmaceutical and cell and gene therapy (CGT) manufacturing.

The new chapter provides practical guidance for assessing the activity of endonucleases derived from Serratia marcescens, an enzyme widely used to reduce host cell DNA and RNA during downstream processing. By establishing a more consistent analytical approach, USP <89.3> supports improved comparability across commercially available endonucleases and helps align testing strategies with current and future pharmacopeial expectations.


To support this initiative, Kerry has implemented the USP <89.3> activity assay for Denarase®, and the corresponding CoA’s now include USP-aligned activity and specific activity values as supplementary information, providing greater transparency and confidence in product performance. 

Adopting USP <89.3> supports regulatory credibility and enables more direct comparison of products available on the market. For manufacturers operating in highly regulated biopharmaceutical and CGT environments, this represents a meaningful step toward clearer quality benchmarks and more informed material selection. 

Please reach out to your Account Manager if you have any questions or if you would like to receive the updated version of the CoA for your specific lot.

Summary of the USP <89.3> Implemation Denarase®:

  • The Problem: Endonuclease activity values reported on suppliers’ CoAs cannot be directly compared due to vendor-specific activity assays.

  • The Solution: USP General Chapter <89.3> provides standardized guidance for determining endonuclease activity and improves comparability across commercially available endonucleases.

  • The Adoption: Kerry has implemented the USP <89.3> assay for Denarase® and will report USP <89.3> parameters on CoAs as additional information while maintaining the established release assay.