The type 2 diabetes drug Invokana hit the market in 2013 with much hype. It was the first drug in a new class of diabetes treatments known as SGLT2 inhibitors. Johnson & Johnson and its unit Janssen Pharmaceuticals, stood to make millions – if not billions – from its novel new diabetes pill. Unlike other diabetes drugs that work through the pancreas or liver, SGLT2 inhibitors are metabolized through the kidneys and lower blood sugar levels by excreting excess sugar through the urine.
Invokana, which contains the drug ingredient canagliflozin, proved to be a huge hit and remains a top seller in the drug class despite other SGLT2 inhibitors entering the market. But, the success of Invokana and some other drugs in the class has been marred by side effects. Here is a list of the five most dangerous ones:
1. Ketoacidosis – Not long after SGLT2 inhibitors hit the market, the FDA warned that the drugs had been linked to reports of ketoacidosis, a serious condition in which too much acid builds up in the blood. If left untreated, ketoacidosis, also known as diabetic ketoacidosis or DKA, can lead to diabetic coma and death.
2. Serious urinary tract infections – Because SGLT2 inhibitors utilize the kidneys and bladder to excrete excess sugar, there was little surprise that the drugs were linked to urinary tract infections during clinical trials. Shortly after the drugs entered the market, the FDA strengthened warnings for serious urinary tract infections that in some cases can result in a serious blood infection called urosepsis, or a kidney infection called pyelonephritis.
3. Bone fractures – People taking Invokana and a similar J&J drug, Invokamet (a combination of canagliflozin and the diabetes drug metformin), have an increased risk of bone fractures, and are also prone to bone mineral density loss.
4. Acute kidney injury ((AKI) – Once again, SGLT2 inhibitors’s novel process of metabolizing through the kidney has led to issues with the kidneys. After the drugs began hitting the market, the FDA strengthened existing warnings regarding AKI and kidney damage with the SGLT2 drugs Invokana, Invokamet, Farxiga and Xigduo.
5. Lower limb amputations – An increased risk for leg and foot amputations – mostly affecting the toes – has been reported in patients taking Invokana and Invokamet. The FDA is currently investigating this risk to determine whether stronger warnings are needed.