Economic Feasibility of the Recovery of Therapeutic Proteins From the Milk of Transgenic Livestock

The recovery of pharmaceuticals from blood plasma is often expensive, limited, and is subject to contamination. The objective of this feasibility study is to present recovery designs and the most significant parameters affecting manufacturing costs of human Serum Albumin (hSA), human Protein C (hPC), and Factor VIII (FVIII) from the milk of transgenic livestock. All the processes presented are based on chromatography columns to achieve separation. The sensitivity of the manufacturing cost of the protein to various parameters are illustrated graphically and discussed, along with the cost distribution percentages for each type of process. It was found that manufacturing costs decrease with superficial velocity, expression levels, column yields, column capacities, and scale of production increases with all other parameters remaining constant. However the estimated cost decreases tend to level out at higher values of the parameters. Finally a judicious choice of separation scheme, such as Fall-Through (FT) versus Direct Adsorption (DA) for hSA production, can decrease the protein cost by as much as 38%, due to savings from wash and elution buffers. The costs associated with the production of hSA (DA process), hSA (FT process), hPC, and FVIII are 3.56, 2.20, 129, and 11,780 $/gr respectively. By means of the optimization of manufacturing parameters to reduce costs, key areas of emphasis for process development were identified.