Type 2 diabetics with glycosylated haemoglobin ( HbA1c ) 7.5 % and 10.5 % , fasting glucose 160 and 240mgdl ( -1 ) , and on stable doses of metformin were evenly randomized to placebo or SRT2104 0.25 g , 0.5 g , 1.0 g or 2.0 g , administered orally once daily for 28days .