Alpha-1-Antitrypsin (AAT) To Treat Emphysema In AAT-Deficient Patients (EXACTLE)

This is a one to one randomized, placebo-controlled, clinical, exploratory study with the aim of collecting information on possible clinical endpoints i.e., the progression of emphysema by lung density measurements with CT scan and frequency of exacerbations that could be used for a subsequent placebo controlled clinical trial. Progression of disease will be investigated in 80 patients with alpha-1-antitrypsin deficiency, who will be treated with human alpha-1-antitrypsin (AAT; Prolastin®) or placebo weekly for two years to analyze the effect of treatment on lung density and exacerbations. Targeted augmentation therapy with weekly infusions of Prolastin® will be a dose of 60 mg/kg body weight (range of 51.72 to 71.43 mg per kg body weight). Therefore, this study focuses on several questions: * Is the 15th percentile point calculated by analysis of CT lung histograms a useful endpoint for clinical trials in AAT deficiency? * Is quantitation of exacerbations in AAT-deficient patients a useful endpoint for clinical trials in AAT deficiency? * Are there significant differences between the treatments in favor of Prolastin®?