Safety and Pharmacokinetics of Alpha-1 Proteinase Inhibitor in Subjects With Alpha1-Antitrypsin Deficiency

The question of whether higher doses of alpha1-PI (\>60 mg/kg) are able to provide better protection to patients with alpha 1-antitrypsin deficiency is currently unknown. As a first step to address this question, the present study has been undertaken. This is a multi-center, randomized, double-blind, crossover study to assess the safety and pharmacokinetics of weekly infusions of 120 mg/kg of Prolastin-C, compared to weekly infusions of 60 mg/kg of Prolastin-C in patients with alpha 1-antitrypsin deficiency. This study is a crossover design with 2 treatment sequences: Treatment Sequence 1: 60 mg/kg weekly infusion of Prolastin-C for 8 weeks followed by 120 mg/kg weekly infusion of Prolastin-C for 8 weeks (starting at Week 1) (total of 16 treatment weeks) Treatment Sequence 2: 120 mg/kg weekly infusion of Prolastin-C for 8 weeks followed by 60 mg/kg weekly infusion of Prolastin-C for 8 weeks (starting at Week 11) (total of 16 treatment weeks) Approximately 15 subjects are planned to be entered into each treatment sequence. At Weeks 8 to 11 and Weeks 18 to 21, a total of 15 serial blood samples for each subject will be drawn for pharmacokinetic analysis. The expected duration of the study subject's participation will be approximately 25 weeks (which includes a 3-Week Screening Phase, 2-Week Washout Period \[between different alpha-1 PI treatment doses\], and a 4-Week Follow-up Period). The following safety parameters will be assessed: adverse events, pulmonary exacerbations, vital signs, pulmonary function tests, and clinical laboratory tests.