(596b) Process Development Tool to Rapidly Predict the Stability of Biopharmaceuticals

Process Development Tool to Rapidly
Predict the Stability of Biopharmaceuticals

S.
Hedberg, Y.
Hutabarat, J. Heng, J. Haigh, D. Williams                

ABSTRACT

Protein aggregation is a critical problem for the
safety of biopharmaceuticals as they are linked to adverse immunologically
related responses in patients. Much effort has been made to gain a better
understanding of aggregation, however, the mechanisms leading to protein
aggregation are still not fully understood. Protein-protein molecular
interactions in solution are known to be involved in protein solution
aggregation behaviour and are a common issue for the manufacturing of biopharmaceuticals
such as monoclonal antibodies, mAbs.  

Therefore, a major industrial and academic challenge
is the development of fast and reliable methods, either theoretically or
experimentally driven, which allow formulation scientists to identify optimal
biopharmaceutical species and solution conditions which deliver stable solution
products, thus avoiding aggregation. The osmotic second virial
coefficient (B₂₂) is a fundamental physiochemical property that
describes the thermodynamics of the protein-protein interactions in solution,
which can be a useful tool for predicting the aggregation propensity of
proteins.

One way of predicting aggregation propensity is
self-interaction chromatography (SIC) that can be used for determining the
osmotic second virial coefficient (B₂₂).
This technique has recently demonstrated to be a tool that can successfully predict
phase behaviour of proteins. However, due to the need to immobilise every
protein in order to make B₂₂ measurements makes this technique less
ideal for use in process development. Another technique, cross-interaction
chromatography (CIC), has shown to be an even more high-throughput technique
than its predecessor with similar capabilities. In CIC only one protein needs
to be immobilised in order to screen a range of other proteins.

In a case study a number of different monoclonal
antibodies from both IgG1 and IgG4 subclasses, and a polyclonal antibody were immobilised
and screened on each of the columns for a wide range of process development
conditions. The aim was to see if the osmotic second virial
cross coefficient (B₂₃) between two proteins can be used to predict
B₂₂.

The results of the case study were very successful
and proved to be a good prediction of the B₂₂ value for all the
proteins in all conditions. This will enable a rapid process development tool with
only mg quantities of biopharmaceutical
species that can be injected on a generic column e.g. a polyclonal IgG column.

Previously, the accuracy of the B₂₂
values of several of the mAbs has been directly
validated by the use of traditional gel filtration chromatography methods and
dynamic light scattering, to investigate the size and quantity of aggregates
over time. This has shown that the determined B₂₂ held powerful
information about the long term stability of biopharmaceuticals.

In summary, this work has developed a rapid and
high-throughput tool, which manages to estimate the B₂₂ values for
different biopharmaceutical products using minimal amounts of protein. This
will help scientists in the biopharmaceutical industry finding suitable
conditions for process development as well as picking drug candidates with high
long term stability.