Linagliptin as add-on therapy to insulin for patients with type 2 diabetes

Type 2 diabetes mellitus (T2DM) is a highly prevalent, progressive disease that often is poorly controlled. The combination of an incretin-based therapy and insulin is a promising approach to optimize the management of glycemic control without hypoglycemia and weight gain. Linagliptin, a recently approved oral dipeptidyl peptidase-4 inhibitor, has a unique pharmacological profile. The convenient, once-daily dosing does not need adjustment in patients with hepatic and/or renal impairment. In clinical studies linagliptin shows an important reduction of blood glucose with an overall safety profile similar to that of placebo. So far, the combination of linagliptin and insulin has been tested in three major clinical studies in different populations. It has been shown that linagliptin is an effective and safe add-on therapy to insulin in patients with T2DM. The efficacy and safety of this combination was also shown in vulnerable, elderly T2DM patients and in patients with T2DM and renal impairment. Favorable effects regarding the counteraction of hypoglycemia make linagliptin especially interesting as an add-on therapy to insulin. This review aims to present the existing clinical studies on the efficacy and safety of linagliptin as add-on therapy to insulin in patients with T2DM in the context of current literature. Additionally, the possible advantages of linagliptin as an add-on therapy to insulin in relation to cardiovascular safety, patient-centered therapy and the prevention of hypoglycemia, are discussed.