Simplified downstream processing for protein therapeutics with rapid custom affinity ligand discovery and affinity resin development

December 14, 2022 / Author:

Scientists continuously face pressure to purify biologics like protein therapeutics with maximum yield while minimizing cost and developing processes as quickly as possible. Downstream processing often accounts for more than half the cost of goods overall and significantly impacts manufacturing timelines.

Affinity chromatography manages to achieve high purity and yield as well as enabling simplified downstream processing. This robust and scalable process architecture de-risks asset development and enables protein purification where less efficient purification steps might fail.

The basis for affinity resin development at Navigo Proteins is the Precision Capturing® technology starting with ligand discovery using artificial Protein A as the underlying scaffold for antibody and non-antibody purification.

Rapid ligand discovery in 6-8 weeks based on high quality scaffold protein libraries

For high-performance resin development, Navigo has implemented and over years continuously optimized a powerful scaffold protein technology platform which yields the desired affinity ligands against the target of choice. Ligand discovery is grounded in a deep understanding of how the scaffold binds to different targets and how to engineer it to open up new binding possibilities.

High quality and diverse libraries created from the artificial Protein A scaffold are generated by randomization of carefully selected surface-exposed residues. Each randomized position can comprise all natural amino acids (except Cysteine) which leads to large combinatorial libraries with complexities of 1010 to 1012 different variants each. These libraries are constantly expanded and are the crucial starting point for ligand discovery programs and subsequent resin development.

Selection and Screening - The optimal ligand for protein therapeutics downstream processing

Ligand discovery is accomplished by phage display to yield ligand-enriched selection pools. The goal is to not only end up with an affinity resin that binds to the target but to develop the ideal resin for respective downstream processing. To choose the ideal affinity ligand from the several thousand candidates discovered in this selection, final conditions during the protein purification process are considered.

A fully automated high-throughput screening platform identifies the desired ligands by rapid screening of up to 15.000 binders per day. A handful of potential optimal ligand candidates for the respective downstream process are then nominated for further development by looking at factors like affinity, stability, specificity, manufacturability, and elution profile.

The most promising leads are selected for further resin development.


Custom affinity resin development in 6-8 weeks

The affinity ligands are coupled to a solid chromatography support (e.g. agarose or polyacrylamide beads) to generate the corresponding custom affinity matrices (resins, membranes, etc.). These prototype resins are rigorously tested for their performance in biologics downstream processing.

Small scale performance testing and lead affinity resin nomination

Resin candidates are thoroughly assessed by Navigo Proteins for performance criteria such as specificity, binding capacity, caustic stability, elution conditions, recovery rate, etc. The best resins are then supplied to the clients for their own internal downstream processing assessment, to confirm resin performance with the actual upstream feed.

The Precision Capturing® resin development does not require an additional leaching assay development because the affinity ligands are recognized by the polyclonal antibodies in commercially available leaching kits.

With the resin development concluded, the final, optimal resin candidate is nominated for scale-up and validation after which the clients’ custom affinity chromatography solution for recombinant protein purification is ready for GMP-compliant clinical and commercial biologics manufacturing.

Reliable resin supply from small to commercial scale, thanks to independent manufacturing partners

Navigo Proteins can supply R&D-grade resin volumes up to 100 ml, to start downstream process development. After this point, resin scale-up and validation is transferred seamlessly to one of Navigo’s commercial-scale manufacturing partners.

The manufacturing partner provides resin up to several hundred-liter scale in pre-packed columns as well as in bulk form for clinical and commercial GMP purification, making Navigo Proteins a one stop shop for custom affinity solutions.


Interested in more information? Then download our whitepaper 'Custom Affinity Chromatography for Commercial Use'.