α-1 antitrypsin deficiency: current and future treatment options

Introduction: alpha-1 antitrypsin deficiency (AATD) is an under-recognised genetic condition, characterised by pulmonary and hepatic disease. It is the most common genetic cause of emphysema. In this review, we discuss the treatment options currently available for AATD, the evidence supporting their use and potential future therapies. Areas covered: We undertake a literature review of the current and developing treatments available for the lung and liver disease associated with AATD, including protein augmentation therapy, gene therapy, molecular chaperones, human-induced pluripotent stem cell (iPSC)-based therapies and organ transplantation. We discuss the cost implications of IV augmentation therapy and the potential for such therapy in 'Z' heterozygotes. Expert opinion: The evidence supporting the administration of IV plasma-purified alpha-1 antitrypsin (AAT) to decrease progression of emphysema in patients with severe AATD has increased. However, it is an expensive and invasive therapy. While augmentation via the aerosol route represents an attractive option, the data supporting its clinical efficacy is lacking. This also applies to gene therapy, chaperones and iPSC-based therapies. In the coming years, there will be increased focus on more effective administration of AAT, the potential for therapy of 'Z' heterozygotes and the use of AAT as an anti-inflammatory.