The goal of this trial was to explore the utility of evaluating emphysema progression through CT scans measuring lung density during a 2 year period of weekly infusions of either placebo or human alpha-1-antitrypsin (AAT; Prolastin®). Exacerbation data recorded in patient diaries were also collected. All efficacy data were analyzed for potential use in evaluating Prolastin efficacy in this and other clinical trials.

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®?

Inclusion Criteria:

• Patient with pulmonary emphysema due to severe congenital AAT deficiency of phenotype protease inhibitor Z (PiZ) or other rare genotypes (not MS, MZ or SZ) and AAT serum level < 11 microns (µM) or < 80 mg/dL (status to be confirmed by phenotyping and genotyping)
• Inspiratory capacity (VC - ERV) > 1.2 L and forced expiratory volume at one second (FEV1) < 80% of predicted value post bronchodilator
• FEV1/VC < 70% of predicted value post-bronchodilator or transfer factor of carbon monoxide (KCO) < 80% of predicted value post-bronchodilator
• History of at least one exacerbation in the past 2 years
• Written informed consent

Exclusion Criteria:

• FEV1 < 25% of predicted value post-bronchodilator
• Augmentation therapy for more than one month with plasma-derived human alpha 1-antitrypsin (AAT) within the last 2 years
• History of lung transplant
• Any lung surgery within the past 2 years
• On any thoracic surgery waiting list
• Diagnosis of liver cirrhosis
• Severe concomitant disease
• Active pulmonary infection/exacerbations within the last month
• Active smoking during the last 6 months or plasma positive for cotinine
• Body weight < 42 kg or > 92 kg
• Pregnancy or lactation
• Women of child-bearing potential without adequate contraception