16 June 2016 

The U.S. Food and Drug Administration (FDA) has strengthened the existing warning about the risk of acute kidney injury for the type 2 diabetes medicines canagliflozin (Invokana) and dapagliflozin (Forxiga). Based on recent reports, FDA has revised the warnings in the drug labels to include information about acute kidney injury and added recommendations to minimize this risk.

Health care professionals should consider factors that may predispose patients to acute kidney injury prior to starting them on canagliflozin or dapagliflozin. These include decreased blood volume; chronic kidney insufficiency; congestive heart failure; and taking other medications such as diuretics, blood pressure medicines called angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), and nonsteroidal anti-inflammatory drugs (NSAIDs).

Assess kidney function prior to starting canagliflozin or dapagliflozin and monitor periodically thereafter. If acute kidney injury occurs, promptly discontinue the drug and treat the kidney impairment.

Canagliflozin and dapagliflozin are prescription medicines used to help lower blood sugar in adults with type 2 diabetes. They belong to a class of drugs called sodium-glucose cotransporter-2 (SGLT2) inhibitors.

From March 2013, when canagliflozin was approved, to October 2015, FDA received reports of 101 confirmable cases* of acute kidney injury, some requiring hospitalization and dialysis, with canagliflozin or dapagliflozin use (see Data Summary). This number includes only reports submitted to FDA, so there are likely additional cases about which we are unaware.

In approximately half of the cases, the events of acute kidney injury occurred within 1 month of starting the drug, and most patients improved after stopping it. Some cases occurred in patients who were younger than 65 years. Some patients were dehydrated, had low blood pressure, or were taking other medicines that can affect the kidneys.

Data Summary:

A search of the FDA Adverse Event Reporting System (FAERS) database from March 29, 2013, to October 19, 2015, identified 101 cases of acute kidney injury with sufficient detail to confirm the diagnosis and demonstrate a temporal relationship with canagliflozin (73 patients) and dapaglifozin (28 patients).

Hospitalization for evaluation and management of acute kidney injury was necessary in 96 of the 101 cases, and 22 cases involved admission to an intensive care unit.

Four deaths occurred during hospitalization, 2 of which were cardiac-related. Fifteen patients received dialysis, and of these, 3 patients had a history of chronic kidney disease or previous acute kidney injury, and 6 reported concomitant use of both an angiotensin-converting enzyme (ACE) inhibitor and a diuretic. In 58 cases, the time to onset of acute kidney injury occurred within one month or less of initiating the drug.

The median age of the patients was 57 years (range 28-79 years). Among the 84 cases that reported an age, more than half were in patients who were 60 years or younger. Of the 101 cases, 51 reported concomitant ACE inhibitor use, 26 reported concomitant diuretic use, and 6 reported concomitant nonsteroidal anti-inflammatory drug (NSAID) use.

A prior history of chronic kidney disease was reported in 10 of the 101 cases. In some cases, dehydration or hypotension was reported. Forty-five of the 101 cases reported a change in renal function (serum creatinine (SCr) or estimated glomerular filtration rate (eGFR)) at the time of diagnosis. The median elevation of SCr from baseline in 32 patients was 1.6 mg/dL. In 13 cases that only reported eGFR at baseline and during the acute kidney injury event, the median decrease in eGFR was 46 mL/min/1.73 m2.

In the 78 cases reporting drug discontinuation, 56 cases reported improvement, demonstrating reversibility of this adverse event in a majority of cases. Eleven patients did not recover, which included the 4 deaths noted previously. Three patients recovered with sequelae upon discontinuation, suggesting that kidney injury may not be fully reversible in some situations.