Canagliflozin is prescribed alongside diet and exercise to help patients with type 2 diabetes lower their blood sugar. It inhibits the sodium-glucose cotrasporter-2, and its effects are measured through the amount of sugar in the patient’s urine, as the drug focuses its effects on the kidneys.
On Tuesday, the FDA concluded that the SGLT2 drug – along with related combos Invokamet and Invokamet XR – caused an increased risk of leg and foot amputations, and it mandated that Johnson & Johnson update its labels accordingly. Regulators are requiring the New Jersey drugmaker to add a black-box warning, the agency’s most serious, to describe the risk, they said.
This heightened warning follows a May 2016 safety alert based on interim data from one of two ongoing trials in which the risk had been seen in one but not the other. Now, final results from both trials indicate an approximate doubling of the risk for both leg and foot amputations in canagliflozin-treated patients compared to those randomly assigned to receive placebo.
The amputations were most commonly of the toe and middle of the foot, but some also involved the leg, below and above the knee. Some patients underwent more than one amputation, and some of those involved both limbs.
The European Medicines Agency has been investigating this phenomenon since April 2016, and in February 2017 issued a requirement that the labels of all drugs of the sodium glucose cotransporter 2 (SGLT2) inhibitor class carry the amputation warning.
Before prescribing canagliflozin, the FDA advises healthcare professionals to consider factors that may predispose patients to amputations, including a history or prior amputation, peripheral vascular disease, neuropathy, and diabetic foot ulcers. Patients taking canagliflozin should be monitored for signs and symptoms of those conditions. The drug should be discontinued if these complications occur.
If you or a loved one use canagliflozin, you should contact a health specialist immediately if there’s any pain or soreness in the legs or feet. Even if ulcers are present, the patient should not stop taking the drug unless a physician indicates otherwise.
As a partner with D'Arcy Johnson Day, Andrew D'Arcy has been involved in some of the nation’s most high-profile cases and investigations. His practice includes serious automobile accidents, medical malpractice, wrongful death and product defect cases. Andrew has been personally responsible for numerous multi-million dollar settlements and verdicts on behalf of his clients. He has been recognized by his peers as an "AV" rated attorney, the highest possible rating given by Martindale-Hubbell publication. Andrew has been named a "Super Lawyer" by New Jersey Monthly magazine each year consistently since 2013.