Optimization of a refolding step for a therapeutic fusion protein in the quality by design (QbD) paradigm.

Production of biotech therapeutics in Escherichia coli involves protein expression as insoluble inclusion bodies that need to be denatured and the resulting protein refolded into the native structure. In this paper, we apply a Quality by Design approach using Design of Experiments for optimization of the refolding process for a recombinant biotech therapeutic, granulocyte colony stimulating factor. First, risk analysis was performed to identify process parameters that require experimental examination.