Phase 1/2, randomized, parallel assignment trial (NCT01304537) evaluating safety and efficacy of alpha-1 antitrypsin (AAT) in T1D. Primary outcomes include incidence of adverse events, beta cell function, exogenous insulin requirements, and HbA1c. Participants will be followed for 12 months post-enrollment (70). This evidence concerns the gene SERPINA1 and type 1 diabetes mellitus.