A class of drugs known as SGLT-2 Inhibitors, used in the treatment of Type 2 diabetes, have come under fire for the serious risks associated with the drugs. The drugs involved are: Janssen's (a subsidiary of Johnson & Johnson) Invokana and Invokamet, AstraZeneca's Farxiga and Xigduo XR and Boehringer Ingelheim's Glyxambia and Jardiance. Rather than metabolizing blood sugars in the body in the way older diabetic drugs do, SGLT-2 inhibitors block reabsorption of the glucose after it passes through the kidneys. Many consider the way in which SGLT-2 drugs use the kidneys to be unnatural, and the process may be a significant factor in the development of diabetic ketoacidosis.
Invokana was the first SGLT-2 inhibitor drug approved by the FDA and is still, far and away, the top seller. Janssen's Invokamet is the same drug as Invokana, combined with an older diabetes drug, Metformin. These two drugs brought in $278 million for Janssen during the first quarter of 2015; Invokana is expected to reach "blockbuster" status in 2015 when it crosses into the billion-dollar annual revenue realm. Farxiga, the second SGLT-2 inhibitor drug to hit the market has the next-highest revenues, bringing in $33 million in 2013, with significant increases since that time.
Have SGLT-2 Inhibitor Drugs Been Marketed for Off-Label Use?
A consumer advocacy group, Public Citizen, wrote a letter to the FDA, urging the agency to fine Janssen, AstraZeneca, Boehringer Ingelheim and other SGLT-2 drug manufacturers for off-label marketing of the drugs. None of the drugs have been approved by the FDA for weight loss, yet advertisements by the manufacturers imply to consumers and to physicians that the drugs have been found to be safe and effective for weight loss.
Because the SGLT-2 inhibitor drugs have been associated with serious side effects, Public Citizen believes the advertisements which promote weight loss may well skewer the risk-benefit calculations made by patients and physicians alike. Because the drugs sport FDA-approved labels in which weight loss is listed as a benefit in the fine print, Janssen has stated their weight loss claims have the blessing of the FDA. There has been no confirmation or denial of that statement from the FDA.
Diabetic Ketoacidosis Associated with SGLT-2 Inhibitor Drugs
Diabetic ketoacidosis most often occurs in those with Type 1 diabetes, also known as juvenile diabetes. When the body becomes unable to use glucose as a fuel source due to the lack of insulin in the body, it begins breaking down fat in the body instead. During this process, a waste product known as ketones build up in the blood and in the urine. Ketoacidosis can be extremely serious, even fatal, and is much less common among patients with Type 2 diabetes--except for those taking SGLT-2 inhibitor drugs.
Because these drugs prevent the kidneys from reabsorbing glucose back into the bloodstream, lower blood glucose levels can occur, with the potential of ketoacidosis developing. The FAERS databases showed twenty cases of diabetic ketoacidosis through June 2014. Since it is generally believed that only 5-10 percent of those who suffer ill effects from a drug or medical device actually file an adverse event report, there could potentially be 500+ cases of ketoacidosis over the past couple of years. SGLT-2 inhibitor drugs are also being prescribed for Type 1 diabetes--even though they are not approved for this use--which can increase the potential for those patients and patients with Type 2 diabetes to develop diabetic ketoacidosis.