Safety of Canagliflozin in Patients with Type 2 Diabetes

Canagliflozin is a newly approved drug for the treatment of type 2 diabetes. This agent lowers blood glucose mainly by increasing urinary glucose excretion through inhibition of sodium glucose co-transporter 2 (SGLT2) in the kidneys. Data derived from randomized clinical trials lasting up to 52 weeks suggest that canagliflozin is generally well tolerated. The most common adverse effects are genital mycotic infections occurring in 11-15% of women exposed to canagliflozin versus 2-4% of those randomized to glimepiride or sitagliptin. In men, corresponding proportions are 8-9% versus 0.5-1%. Urinary tract infections (UTI) are slightly increased (5-7%) with the use of canagliflozin compared with placebo (4%). The risk of hypoglycemia associated with canagliflozin is marginally higher than placebo, but markedly increases when the drug is used in conjunction of insulin or sulfonylureas (SU), in patients with chronic kidney disease (CKD), and in the elderly. Worsening renal function and hyperkalemia may occur in patients using canagliflozin, particularly in patients with underlying CKD. Mild weight loss (mean 2-4 kg) and lowering of blood pressure represent 2 advantages of canagliflozin owing to its osmotic diuretic effect. However, the latter action may lead to postural hypotension and dizziness in susceptible subjects. Another concerning adverse effect of canagliflozin is an average 8% increase in plasma levels of low-density lipoprotein cholesterol (LDL-C) compared with placebo. Overall, canagliflozin is a useful addition for treatment of type 2 diabetes, but its safety needs to be established in long-term clinical trials.