The perils of clinical trials.

When the maximal reabsorptive capacity for glucose is lowered by blockade of the activity of sodium-glucose cotransporter-2 (SGLT2), glucosuria occurs in proportion to the plasma glucose and glomerular filtration rate. Accordingly, the modest, 0.44%, hemoglobin A1c reduction found by Kohan et al. in diabetic patients with relatively good glycemic control and chronic kidney disease stage 3 treated with an SGLT2 inhibitor might have been anticipated. The 0.32% fall in hemoglobin A1c in the placebo group, however, seems less expected.