New insulins in the treatment of diabetes mellitus

Landmark studies have confirmed the importance of intensified insulin treatment for minimizing long-term diabetic complications. Human insulin is still first-line treatment. However, even the most intensive of human insulin-based regimens can only poorly reproduce physiologically desirable insulin release, which includes rapid outbursts of insulin at mealtimes coupled with relatively low and stable basal levels between meals. Encouragingly, there are now four available or soon-to-be-available insulin analogues that offer the potential for more physiological insulin profiles. Insulin lispro and insulin aspart are rapid-acting insulin analogues intended for immediate pre-meal administration in type 1 or type 2 diabetes. Compared with injected human insulin, they improve post-prandial glucose control and reduce late post-meal and night-time hypoglycaemic episodes. Two basal insulin analogues, insulin glargine and insulin detemir, have also shown beneficial profiles with regard to night-time hypoglycaemia. Some, but not all, studies with the two rapid-acting insulins have shown improvement in overall glucose control, as assessed by HbA1c, in comparison to human insulin. These results are encouraging and provide hope that entirely analogue-based regimens may improve overall glycaemic control and ease of use of insulin.