Invokamet Flesh-Eating Infection Led To Scrotum Amputation, Lawsuit Alleges

Following recent warnings issued by federal regulators about the risk of flesh eating infections from Invokana and similar diabetes drugs, a Connecticut man has filed a product liability lawsuit alleging that he experienced problems resulting in a partial scrotum amputation after using Invokamet, which contains the same active ingredients.

The complaint (PDF) was filed by Lee Letourneau in the U.S. District Court for the District of New Jersey on September 6, indicating that he developed Fournier’s gangrene following use of Invokamet, which combines Invokana with the older diabetes drug metformin.

Letourneau indicates that he began taking Invokamet in February 2017, and took the diabetes medication throughout most of the year. However, after taking the drug he contracted the flesh-eating infection, which can be life-threatening, and ultimately had to undergo surgical removal of about 60% of his scrotum.

According to allegation raised in the Invokamet lawsuit, Johnson & Johnson and it’s Janssen Pharmaceuticals subsidiary failed to adequately warn consumers and the medical community about the risk of developing Fournier’s gangrene or other infections. Letourneau indicates that he was unaware his infection was linked to the use of Invokamet until an FDA warning issued last month.

The agency issued a drug safety communication on August 29, indicating that Invokana, Invokamet and similar diabetes drugs have been linked to reports of the rare, but serious, genital infections. The Fournier’s gangrene cases, which are also known as necrotizing fasciitis of the perineum, can be life threatening and eat through flesh. The FDA noted that while diabetes can increase the risk of the infections, the problems are still rare among diabetic patients not taking Invokana or similar drugs.

It is likely that the number of reported cases involving Invokana flesh-eating infections may increase as awareness of the connection becomes known, according to the lawsuit.

“Defendants’ label for Invokamet does not contain a warning for Fournier’s gangrene. The label states only that gangrene may be a complication associated with lower limb amputations,” the lawsuit indicates. “It also states that animal studies were not conducted for Invokamet, but that in animal studies of canagliflozin and metformin individually, there were incidents of testicular tumors. Nowhere does the label state that a male patient might suffer Fournier’s gangrene, or lose part of his scrotum.”

Following the safety alert, the FDA is requiring new label warnings be added to all drugs that belong to the class, including Invokana, Invokamet, Invokamet XR, Farxiga, Xigduo XR, Qtern, Jardiance, Glyxambi, Synjardy, Synjardy XR, Steglatro, Segluromet and Steglujan. Steglatro is the only drug that has not been linked to a case of flesh-eating genital infection, but the agency is requiring it to carry a label warning anyway.

The agency indicates that the infections developed within several months of beginning treatment with one of the drugs and all 12 patients underwent hospitalization and surgery. According to the FDA’s findings, at least one patient died, while others suffered multiple disfiguring surgeries and other complications.

Other Health Concerns Linked To Invokana and Similar Drugs

The flesh-eating genital infection warning is just the latest adverse health risk added to Invokana and similar drugs since they were first introduced on the market. The previous warnings have included kidney failure, diabetic ketoacidosis and amputations (specifically for Invokana). The drugs did not carry warnings for any of those risks when they were first approved by the FDA.

Invokana (canagliflozin) was the first SGLT-2 inhibitor introduced to the market, which was approved in March 2013 and quickly became a blockbuster treatment. The medication works in a unique way, impacting some normal kidney functions to help remove glucose from the body through urine.

In December 2015, the FDA required Johnson & Johnson to add new diabetic ketoacidosis warnings to Invokana and similar drugs, indicating that the medications increase the risk of this serious condition, which typically results in the need for emergency treatment to avoid life-threatening injury. Prior to the update, the warnings failed to alert consumers about the importance of seeking immediate medical attention if they experience symptoms like abdominal pain, fatigue, nausea, respiratory problems or vomiting.

In June 2016, the FDA required additional label warnings about the link between kidney risks and Invokana and other drugs from its class, indicating that the medications may increase the risk of acute kidney injury and other severe health problems.

In May 2017, FDA required new warnings about the Invokana amputation risks, adding information to the drug label about the increased incidence of leg, foot and toe amputations. That warning was only required for Invokana, and manufacturers of other SGLT-2 inhibitors have suggested that Invokana leg and foot amputation problems were unique to that drug, maintaining that the same risks were not seen among users of their medications.

Johnson & Johnson and Janssen face several thousand other Invokana lawsuits, which allege that users and the medical community were not provided adequate warnings at the time the drug was first introduced. The makers of other diabetes drugs from the same class, including Farxiga and Xigduo XR, have also faced similar lawsuits; though most have been filed against the makers of Invokana.

The FDA indicates that there were 1.7 million prescriptions dispensed for SGLT2 inhibitors in 2017. The agency requests anyone who has suffered side effects after taking one of these drugs file a report with the FDA MedWatch adverse event reporting system.