2. Cohort 2 - Individuals on dual therapy (metformin plus repaglinide, a sulphonylurea or pioglitazone) will be randomised (1:1) to either continuation of their current therapy or to switch to metformin and Canagliflozin (Invokana™) Randomisation will be stratified by site and entry therapy (monotherapy OR dual therapy which includes metformin plus pioglitazone, or metformin plus either a sulphonylurea or repaglinide, respectively) resulting in 6 stratification groups. Randomisation will not be carried out until after the baseline data have been collected.