Demonstrating Analytical Similarity of Trastuzumab Biosimilar HLX02 to Herceptin® with a Panel of Sensitive and Orthogonal Methods Including a Novel FcγRIIIa Affinity Chromatography Technology

A biosimilar needs to demonstrate its similarity to the originator reference product (RP) in terms of structural and functional properties as well as nonclinical and clinical outcomes. Objectives: The

Besides having an overall high analytical similarity to both EU-Herceptin® and CN-Herceptin®, HLX02 is more similar to Herceptin® with high FcγRIIIa affinity, a result that demonstrates the power of the novel FcγRIIIa affinity chromatography technology in biosimilarity evaluation.

A panel of highly sensitive and orthogonal methods, including a novel Fc gamma receptor IIIa (FcγRIIIa) affinity chromatography technique that enables quantitative comparison of glycan effects on effector function, was developed for the assessment. To ensure the full product variability was captured, ten batches of HLX02 were compared with 39 RP batches with expiry dates from August 2017 to March 2021.

The extensive three-way similarity assessment demonstrated that HLX02 is highly similar to the RPs. Furthermore, the %afucose, %galactose, and FcγRIIIa affinity of the RPs were observed to first decrease and then return to the original level in relation to their expiry dates, and the RP batches can be subgrouped by their FcγRIIIa affinity chromatograms. HLX02 is demonstrated to be more similar to the RPs of the high FcγRIIIa affinity group.