Initiating insulin therapy in type 2 diabetes: A comparison of biphasic and basal insulin analogs

OBJECTIVE - Safety and efficacy of biphasic insulin aspart 70/30 (BIAsp 70/30, prebreakfast and presupper) were compared with once-daily insulin glargine in type 2 diabetic subjects inadequately controlled on oral antidiabetic drugs (OADs). RESEARCH DESIGN AND METHODS - This 28-week parallel-group study randomized 233 insulin-naive patients with HbA_1c values ≥8.0% on > 1,000 mg/day metformin alone or in combination with other OADs. Metformin was adjusted up to 2,550 mg/day before insulin therapy was initiated with 5-6 units BIAsp 70/30 twice daily or 10-12 units glargine at bedtime and titrated to target blood glucose (80-110 mg/dl) by algorithm-directed titration. RESULTS - A total of 209 subjects completed the study. At study end, the mean HbA_1c value was lower in the BIAsp 70/30 group than in the glargine group (6.91 ± 1.17 vs. 7.41 ± 1.24%, P < 0.01). The HbA_1c reduction was greater in the BIAsp 70/30 group than in the glargine group (-2.79 ± 0.11 vs. -2.36 ± 0.11%, respectively; P < 0.01), especially for subjects with baseline HbA_1c >8.5% (-3.13 ± 1.63 vs. -2.60 ± 1.50%, respectively; P < 0.05). More BIAsp 70/30-treated subjects reached target HbA_1c values than glargine-treated subjects (HbA_1c ≤6.5%: 42 vs. 28%, P < 0.05; HbA_1c <7.0%: 66 vs. 40%, P < 0.001). Minor hypoglycemia (episodes/year) was greater in the BIAsp 70/30 group than in the glargine group (3.4 ± 6.6 and 0.7 ± 2.0, respectively; P < 0.05). Weight gain and daily insulin dose at study end were greater for BIAsp 70/30-treated subjects than for glargine-treated subjects (weight gain: 5.4 ± 4.8 vs. 3.5 ± 4.5 kg, P < 0.01; insulin dose: 78.5 ± 39.5 and 51.3 ± 26.7 units/day, respectively). CONCLUSIONS - In subjects with type 2 diabetes poorly controlled on OADs, initiating insulin therapy with twice-daily BIAsp 70/30 was more effective in achieving HbA_1c targets than once-daily glargine, especially in subjects wit hHbA_1c >8.5%.