Lung gene therapy: Clinical and regulatory issues

Lung gene therapy is a promising therapeutic approach for several difficult to treat disorders such as cystic fibrosis, α1-antitrypsin deficiency, and cancers. Although several gene therapy protocols have proven success in preclinical studies, when moved to the clinical stages, they have met with limited success. Thus, there is a need to carefully assess the developmental approaches undertaken with gene therapy products intended for lung disorders. This review summarizes the advances made in lung gene therapy, discusses the limitations of the existing approaches including the lack of reliability of preclinical studies, immunogenecity and toxicity of the gene therapy vectors, and the poor efficiency of nonviral vectors, and invokes the role of ethics and the regulatory agencies in better developing the gene therapy products.