Amputation Risk Associated with Invokana Reported by FDA
In July 2017, an FDA-mandated cardiovascular outcomes trial (CANVAS) reported that Invokana use roughly doubles the risk of lower limb amputation (although lowering the risk of serious cardiovascular events). The findings of amputation risk prompted the FDA to order a black box warning for the drug. The data from CANVAS does not indicate why amputations are being seen years after the trials leading to the FDA’s original approval of Invokana to lower glucose.
Invokana is Johnson & Johnson’s brand name for canagliflozin, a type 2 diabetes drug approved by the FDA in March 2013. Invokana and other SGLT2 inhibitors lower blood sugar by causing the kidneys to excrete glucose through the patients’ urine, reducing the amount of glucose in the patients’ blood. However, the patients’ kidneys have been found to also excrete crucial blood components, allegedly leading to severe complications and side effects.