Canagliflozin, Newly Approved for Type 2 Diabetes, Appears to Be Effective

When metformin monotherapy fails to control type 2 diabetes, the best choice for a second agent is unclear. The FDA recently approved another option: the novel agent canagliflozin (Invokana), which lowers plasma glucose by inhibiting renal sodium–glucose cotransporter 2 and thereby promoting glycosuria.

In a double-blind, manufacturer-supported study, 1450 adults with type 2 diabetes who were receiving metformin monotherapy (glycosylated hemoglobin [HbA_1c] levels, 7.0%–9.5%) were randomized to add either glimepiride (mean final daily dose after up-titration, 5.6 mg) or one of two daily doses of canagliflozin (100mg or 300 mg).

After 52 weeks, patients who received higher-dose canagliflozin achieved a modestly but significantly greater reducti…