Beyond freeze-drying of biologics: vacuum-foam drying and spray freeze-drying

The complexity of biotherapeutics in development continues to increase as our capability in discovery and recombinant technology improves. While safety and efficacy remain the two critical aspects of all therapeutics, ensuring adequate stability is a challenge. Freeze-drying is a commonly-used processing technique to enhance the stability of biotherapeutic products, although the lengthy process time and low energy efficiency have led to the search for, and evaluation of, next-generation drying technologies, including spray freeze-drying and vaccum-foam drying. Both processes result in dosage forms that vary considerably from those produced by lyophilization and possess physical properties that may be deemed superior for their intended applications. Keywords: vacuum-foam drying; spray freeze-drying; lyophilization; biotherapeutics; stabilization