Pramlintide + Insulin in Closed Loop System Improves Glucose Control

To examine whether preprandial injections of pramlintide, an analog of the naturally-occurring beta-cell peptide amylin, would improve postprandial glycemia by delaying gastric emptying, Stuart A. Weinzimer, M.D., from the Yale University School of Medicine in New Haven, Conn., and colleagues treated eight patients with type 1 diabetes (15 to 30 years old) with a closed-loop insulin delivery system for 24 hours either alone or plus preprandial injections of 30 µg pramlintide.

The researchers found that the addition of pramlintide significantly increased the mean time to peak blood glucose (2.5 versus 1.5 hours). The addition of pramlintide also significantly reduced the mean magnitude of glycemic excursion (88 versus 113 mg/dL), with the reduction being particularly pronounced at lunch and dinner, when premeal insulin concentrations were higher.

"Pramlintide delayed the time to peak postprandial blood glucose and reduced the magnitude of prandial blood glucose excursions," Weinzimer and colleagues conclude. "Beneficial effects of pramlintide on closed-loop may in part be related to higher premeal insulin levels at lunch and dinner compared with breakfast."