In this project our client needed a comparison of the impurity profile of their mAb biosimilar to that of the originator product. Interestingly, our SWATH LC-MS analysis identified several host cell proteins (HCPs) in the originator drug product batches, not found in the biosimilar.
The client is a multinational, biopharmaceutical company, focusing on developing best-in-class biosimilar medicines. Their observations showed a difference in drug stability when comparing originator to biosimilar where the latter was more stable. The client was thus particularly interested in investigating the impurity profile to explain the stability differences.
The importance of looking for problematic HCPs
Especially one HCP, which we identified in the originator, caught our eye. It is a protease that may decrease the stability of the therapeutic protein. This specific protease belongs to a group of enzymes known to cleave various recombinant proteins, such as antibody fragments, monoclonal antibodies, bispecific antibodies, and fusion proteins.
Therefore, it is considered potentially problematic and must be identified and removed, to increase shelf life. Moreover, increased stability is not only a safety issue but often also affects the Cost of Goods Sold (COGS). Thus, better stability may result in large economic savings during the life span of the drug product.
No problematic HCPs detected in biosimilar
We also analyzed the biosimilar product by mass spectrometry. Hence, we could inform our client that their product did not contain any detectable HCPs known to be problematic. This knowledge thus supplied them with extra ammunition for regulatory documentation. Also, they now had further sales arguments on why you should choose their product over the originator.