The DURAbility of Basal versus Lispro mix 75/25 insulin Efficacy (DURABLE) Trial

OBJECTIVE This study compared the durability of glycemic control of twice-daily insulin lispro mix 75/25 (LM75/25: 75% insulin lispro protamine suspension/25% lispro) and once-daily insulin glargine, added to oral antihyperglycemic drugs in type 2 diabetes patients. RESEARCH DESIGN AND METHODS During the initiation phase, patients were randomized to LM75/25 or glargine. After 6 months, patients with A1C ≤ 7.0% advanced to the maintenance phase for ≤ 24 months. The primary objective was the between-group comparison of duration of maintaining the A1C goal. RESULTS Of 900 patients receiving LM75/25 and 918 patients receiving glargine who completed initiation, 473 and 419, respectively, had A1C ≤ 7.0% and continued into maintenance. Baseline characteristics except age were similar in this group. Median time of maintaining the A1C goal was 16.8 months for LM75/25 (95% CI 14.0-19.7) and 14.4 months for glargine (95% CI 13.4-16.8; P = 0.040). A1C goal was maintained in 202 LM75/25-treated patients (43%) and in 147 glargine-treated patients (35%; P = 0.006). No differences were observed in overall, nocturnal, or severe hypoglycemia. LM75/25 patients had higher total daily insulin dose (0.45 ± 0.21 vs. 0.37 ± 0.21 units/kg/day) and more weight gain (5.4 ± 5.8 vs. 3.7 ± 5.6 kg) from baseline. Patients taking LM75/25 and glargine with lower baseline A1C levels were more likely to maintain the A1C goal (P = 0.043 and P < 0.001, respectively). CONCLUSIONS A modestly longer durability of glycemic control was achieved with LM75/25 compared with glargine. Patients with lower baseline A1C levels were more likely to maintain the goal, supporting the concept of earlier insulin initiation.