Randomized Trial of Continuous Subcutaneous Delivery of Exenatide by ITCA 650 Versus Twice-Daily Exenatide Injections in Metformin-Treated Type 2 Diabetes
OBJECTIVE
To evaluate ITCA 650, a continuous subcutaneous miniature osmotic pump delivery system of exenatide versus twice-daily exenatide injections (Ex-BID) in subjects with type 2 diabetes.


RESEARCH DESIGN AND METHODS
We conducted a randomized, two-stage, 24-week, open-label, phase 2 study in type 2 diabetes inadequately controlled with metformin. Stage I: 155 subjects were randomized to 20 or 40 μg/day of ITCA 650 or Ex-BID 5 → 10 μg. Stage II: 131 subjects were rerandomized to 20, 40, 60, or 80 μg/day of ITCA 650. Change from baseline for HbA1c, weight, and fasting plasma glucose were evaluated at weeks 12 and 24.


RESULTS
HbA1c was significantly lower in all groups after 12 and 24 weeks. Stage I: mean change in HbA1c from a mean baseline of 7.9-8.0% was -0.98, -0.95, and -0.72% for the 20 and 40 μg/day ITCA 650 and Ex-BID groups, respectively, with 63, 65, and 50% of subjects achieving HbA1c levels ≤ 7% (P < 0.05). Stage II: significant (P < 0.05) reductions in HbA1c (≈ 1.4% from baseline) were achieved with 60 and 80 μg/day ITCA 650, and 86 and 78% of subjects achieved HbA1c ≤ 7% at 24 weeks; respectively. Weight was reduced by 2.8-3.7 kg (P < 0.05) at 24 weeks in all except the 20 → 20 μg/day group. ITCA 650 was well tolerated; nausea was lower and transient with 20 μg/day relative to Ex-BID; and 60 μg/day had the best profile of tolerability and HbA1c lowering.


CONCLUSIONS
ITCA 650 significantly reduced HbA1c and weight and was well tolerated. The 20 → 60 μg/day regimen was considered the best dose for further examination in phase 3.