These insulins meet the needs for bolus insulin but, all of the studies done with these preparations show that you have to combine a good bolus insulin with a good basal insulin. To date, we haven't had one. The absence of a good basal insulin is magnified when you use the very short-acting preparations. With insulin lispro, postprandial glucose is reduced very effectively, but by the next meal, the blood glucose is elevated, and fasting glucose levels are elevated. Currently, the only way to provide basal insulin is with an insulin pump.
Pumps are expensive, however, and there are problems with complications and adherence.
So they really aren't a universally applicable form of therapy. Probably the first basal insulin to reach the market in the United States will be a preparation called insulin glargine. It is being reviewed by the Food and Drug Administration now, with anticipated release in the late spring of 2000. Other basal insulins are also in development, including one called NN304, or insulin detemir. The concept with the basal insulins is to modify the insulin molecule in a way that produces a flat insulin absorption curve.