Initiating insulin therapy in type 2 Diabetes: a comparison of biphasic and basal insulin analogs

Abstract

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 with HbA(1c) >8.5%.