U300, a novel long-acting insulin formulation.

INTRODUCTION: Insulin glargine (100 U/ml; U100) was the first long-acting basal insulin analog to be introduced into clinical practice and it remains the most widely used. Although U100 is an effective and safe treatment, research is ongoing to optimize the time-action profile. The focus of this review is insulin glargine [rDNA origin] injection 300 U/ml (U300), a novel formulation that contains a higher concentration of insulin than U100. AREAS COVERED: The clinical efficacy and safety of U300 in patients with type 1 and type 2 diabetes mellitus are discussed, with an emphasis on recently released data from the Phase III EDITION clinical trials. EXPERT OPINION: The higher concentration of insulin in U300 results in a distinct pharmacokinetic and pharmacodynamic profile. U300 has a longer duration of action than U100 and plasma insulin exposure is less variable. Both insulin formulations exhibit a similar efficacy and safety profile, but importantly, U300 is associated with less body weight gain and a lower incidence of hypoglycaemic events.