Insulin degludec versus insulin glargine in insulin-naive patients with type 2 diabetes: a 1-year, randomized, treat-to-target trial (BEGIN Once Long)

Objective: To compare ultra-long-acting insulin degludec with glargine for efficacy and safety in insulin-naive patients with type 2 diabetes inadequately controlled with oral antidiabetic drugs (OADs).

Research design and methods: In this 1-year, parallel-group, randomized, open-label, treat-to-target trial, adults with type 2 diabetes with A1C of 7-10% taking OADs were randomized 3:1 to receive once daily degludec or glargine, both with metformin. Insulin was titrated to achieve prebreakfast plasma glucose (PG) of 3.9-4.9 mmol/L. The primary end point was confirmation of noninferiority of degludec to glargine in A1C reduction after 52 weeks in an intent-to-treat analysis.

Results: In all, 1,030 participants (mean age 59 years; baseline A1C 8.2%) were randomized (degludec 773, glargine 257). Reduction in A1C with degludec was similar (noninferior) to that with glargine (1.06 vs. 1.19%), with an estimated treatment difference of degludec to glargine of 0.09% (95% CI -0.04 to 0.22). Overall rates of confirmed hypoglycemia (PG <3.1 mmol/L or severe episodes requiring assistance) were similar, with degludec and glargine at 1.52 versus 1.85 episodes/patient-year of exposure (PYE). There were few episodes of nocturnal confirmed hypoglycemia in the overall population, and these occurred at a lower rate with degludec versus glargine (0.25 vs. 0.39 episodes/PYE; P = 0.038). Similar percentages of patients in both groups achieved A1C levels <7% without hypoglycemia. End-of-trial mean daily insulin doses were 0.59 and 0.60 units/kg for degludec and glargine, respectively. Adverse event rates were similar.

Conclusions: Insulins degludec and glargine administered once daily in combination with OADs provided similar long-term glycemic control in insulin-naive patients with type 2 diabetes, with lower rates of nocturnal hypoglycemia with degludec.