The majority of protein therapeutics continue to be delivered through IV administration due to the requisite high doses. Enabling subcutaneous delivery of protein therapies often requires technologies capable of delivering up to gram quantities of protein.

High concentration formulations are often limited by protein stability and solution viscosity. As an alternative approach, suspension formulations comprised of solid-state protein particles suspended in non-aqueous vehicles can provide a platform approach to enable ultra-high protein concentrations. Using spray drying, a versatile and high throughput operation, we demonstrate how particle engineering and formulation development can be optimized together for delivery and protein stability.

This case study, addressing protein stability and suspension viscosity, presents the development of a high concentration bevacizumab suspension at up to 400-500 mg/mL for suitable subcutaneous delivery of the monoclonal antibody (mAb) therapy.

KEY TAKEAWAYS:

1. Spray dried protein suspensions provide a suitable platform for achieve high concentration doses of > 400 mg/mL
2. By optimizing particle properties, target dispense forces can be achieved at these high protein concentrations
3. High concentration bevacizumab suspensions demonstrate stability at refrigerated conditions out to 6 months with proper vehicle selection