Optimization of PLGA formulation containing protein or peptide-based antigen: Recent advances.

Protein or peptide-based antigens are the most promising forms to generate custom protective immune responses for clinical applications. Over the last decades, poly(lactic-co-glycolic acid) (PLGA) as a biodegradable polymer has gained more attention for delivery of protein and peptide. Besides many appropriate characteristics, to improve its properties to overcome some obstacles such as release profile and it is important instability of antigen during both encapsulation and storage. Therefore, optimized procedures conditions require to be used to maintain the integrity of protein structure under several stress factors in formulation process. In this review article, the properties of PLGA particles, their preparation techniques and strategies for improvement of protein stability during encapsulation into PLGA, release from particle and storage as well as stabilization approaches were summarized.