Another vaccine targeting type 1 diabetes mellitus, BHT-3021, which completed its phase I trial in the United States, Australia, and New Zealand [53], gained its effect through delivering a proinsulin-encoding DNA plasmid to antigen-presenting cells, leading to antigen presentation without co-stimulation and subsequent induction of immune tolerance in proinsulin-reactive T-cells [54]. This evidence concerns the gene INS and type 1 diabetes mellitus.