Metformin is currently the standard first-line treatment for patients with type 2 diabetes. However, it is known that metformin is not tolerated at high doses in all patients (metformin is associated with dose-related side effects such as diarrhoea, nausea and abdominal bloating, and a potential risk for lactic acidosis), thus limiting metformin use across the range of patients with type 2 diabetes. This study suggests that linagliptin would be a valuable treatment also in this type 2 diabetes population for whom metformin therapy is inappropriate due to contraindications and intolerability, including patients with renal impairment.

Safety and efficacy of linagliptin as add-on therapy to an SU in inadequately controlled type 2 diabetes patientsIn the other phase III study presented at the EASD Annual Meeting, linagliptin 5 mg was assessed in an 18-week, multi-centre, randomised, double-blind, placebo-controlled, parallel-group design to determine the efficacy, safety and tolerability of linagliptin as add-on therapy to sulphonylurea (SU) in patients with type 2 diabetes and insufficient glycaemic control.

An earlier phase III study in over 1,000 patients had demonstrated significant improvements in glycaemic control when linagliptin was added to the combination of metformin and an SU (mean placebo adjusted HbA1c reduction was -0.6%; p<0.0001).7 The new study, although conducted in a smaller patient group>1c from baseline (mean placebo adjusted HbA1c reduction -0.5%; p<0.0001), thus further supporting the efficacy of linagliptin as add-on therapy.

Further, the trial results showed an overall incidence of adverse events similar to placebo (42.2% versus 42.9% respectively) and, importantly, there was no significantly increased risk for hypoglycaemia when linagliptin was added to SU background therapy (5.6% in the linagliptin group versus 4.8% in the placebo group). The percentage of participants requiring rescue therapy in the linagliptin group was only half the proportion of those requiring rescue therapy in the placebo group (7.6% versus 15.9%). No significant difference in change in body weight was observed between the groups. The safety results from this study are an important finding as sulphonylureas are associated with side effects such as weight gain and risk of hypoglycaemia which could be exacerbated with uptitration of the SU agent. The study concluded that linagliptin has the potential to be used safely as add-on therapy in type 2 diabetes patients with insufficient gylcaemic control on sulphonylurea alone.

Source : Boehringer Ingelheim