Are newer insulins always the better option?

Since its discovery almost a century ago, there have been numerous advancements in the formulations of insulin. The newer insulin analogs have structural modifications with the goal of altering pharmacokinetics to achieve either quick onset and offset of action (mealtime bolus analogs), or a prolonged steady action (basal analogs). These analogs offer many advantages over older human insulins but are several-fold more expensive. The aim of this review is to evaluate reasons for the exorbitant price of the newer insulins, to examine the evidence regarding their clinical advantages and to make value-based prescribing recommendations.

The higher cost of newer insulins cannot be justified based on drug development or manufacturing costs. Compared with older insulins, newer analogs do not offer significant advantage in achieving hemoglobin A1c targets, but they reduce risk of hypoglycemia. The reductions in hypoglycemia are relatively modest and most apparent in those with type 1 diabetes, possibly because these individuals are more prone to hypoglycemia.

When cost considerations are important, the older insulins (regular and NPH insulin) can be used safely and effectively for most individuals with type 2 diabetes who have a low risk of hypoglycemia.