Data from three Phase 3 studies were analysed , in which : ( Study 1 ) canagliflozin 100 and 300 mg were compared with placebo as monotherapy for 26 weeks ; ( Study 2 ) canagliflozin 100 and 300 mg were compared with placebo as add-on to metformin + sulfonylurea for 26 weeks ; or ( Study 3 ) canagliflozin 300 mg was compared with sitagliptin 100 mg as add-on to metformin + sulfonylurea for 52 weeks .