Human Proinsulin Normalizes Fasting Hyperglycemia in Patients With NIDDM

Human proinsulin (HPI) acutely lowers plasma glucose (PG) with 8% of the potency of insulin on a molar basis (1). Studies have shown the duration of action of HPI is longer than that of insulin, and its ability to suppress hepatic glucose production is 50% greater than its ability to stimulate glucose uptake compared with insulin (2). These data suggest that HPI may have a role in the treatment of patients with non-insulin-dependent diabetes mellitus (NIDDM). We compared the efficacy of HPI versus sulfonylureas in chronically (6 mo) controlling glycemia in patients with NIDDM who had previously not been adequately controlled on sulfonylureas.