Formulation technologies to overcome unfavorable properties of peptides and proteins for pulmonary delivery

The pulmonary delivery of peptides and proteins has been considered as a promising alternative administration route to injections. Several advanced formulation technologies have been developed to deliver peptide and protein drugs to and through the lungs by overcoming the unfavorable properties of these macromolecular drugs. Some of them have shown the great potential; however, none of them is flawless. The future innovation in pulmonary delivery for biopharmaceuticals may lie in better understanding of interplay between the lung biology and the advanced formulation technologies.