Patients with Type 2 diabetes who take the prescription medication Invokana (canagliflozin) either experience “significantly improved renal outcomes” or risk severe kidney damage – depending on which study you believe.

In a press release issued last week, drug maker Janssen Pharmaceuticals reported new results from the company’s ongoing CANVAS clinical trials, which were presented at the annual meeting of the American Society of Nephrology. According to that study, Invokana “reduced the risk of kidney disease progression” when compared to the placebo over a six-year period for patients who suffer from cardiovascular disease or are at risk of developing the condition.

Blood tests showed that subjects initially experienced a decline in the flow rate of filtered liquids through their kidneys (known as their “globular filtration rate,” or GFR). However, over the course of the study, these levels gradually improved. At the same time, patients who took a placebo saw a reduction in their GFR.

The CANVAS study also demonstrated “no increase in renal adverse events…including acute kidney injury and hyperkalemia [elevated potassium levels]” among the Invokana group.

An independent analysis of reports contained in the FDA’s adverse event database indicated something else altogether. According to that study, Invokana and other medications of the SGLT-2 inhibitor class (which includes Farxiga [dapagliflozin] and Jardiance [empagliflozin]) are linked to acute renal failure.

The analysis, published last month in the journal Nutrition, Metabolism & Cardiovascular Diseases, looked at nearly 19,000 adverse event reports submitted to the FDA between 2013 and 2016. Of those cases, 6.5 percent involved kidney failure; more than 40 percent of those patients required extended hospital stays, and 16 of the patients died. In over 96 percent of those cases, SGLT-2 inhibitors such as Invokana were determined to be either the primary or secondary cause. Furthermore, SGLT-2 inhibitors were linked to higher percentages of acute kidney failure when compared with alternative treatments.

Of the three SGLT-2 inhibitors studied in the analysis, Invokana was associated with a significantly greater number of kidney failures than Farxiga or Jardiance.

There were other factors involved as well, including gender, obesity and the use of diuretics and ACE inhibitors used to treat hypertension.

When first introduced, Invokana was hailed as a “wonder drug,” enabling diabetics to control their glucose levels simply by passing it in their urine. However, several reputable experts expressed serious concerns early on. These concerns were expressed both to the manufacturer and the FDA, but the drug was nonetheless approved for the market in 2013.

Since that time, there have been more than 860 lawsuits filed against Janssen Pharmaceuticals and parent company Johnson & Johnson by patients who have suffered serious injuries, including kidney failure and related complications, as a result of taking Invokana.

Plaintiffs allege that both companies were well aware of the dangers of their product, and deliberately concealed this information from patients and their doctors. Approximately 775 of these cases have been consolidated into multi-district litigation before a U.S. federal court. The next pretrial hearing on how the cases will proceed is scheduled for the second week of January.

K.J. McElrath is a former history and social studies teacher who has long maintained a keen interest in legal and social issues. In addition to writing for The Ring of Fire, he is the author of two published novels: Tamanous Cooley, a darkly comic environmental twist on Dante's Inferno, and The Missionary's Wife, a story of the conflict between human nature and fundamentalist religious dogma. When not engaged in journalistic or literary pursuits, K.J. works as an entertainer and film composer.