A pharmaceutical watchdog organization is recommending re-evaluation of the clinical value of Lipitor in light of its tendency to increase the risk of type-2 diabetes in women.

In the Annual Report Issue of the Quarter Watch Report published by the Institute for Safe Medication Practices, the Institute reports that in 2014 Lipitor side effects were the subject of more legal claims than those of any other drug.

The Quarter Watch report covers medication-related adverse events that are reported to the FDA’s Adverse Event Reporting System. These events include legal claims filed over a particular drug.

Lipitor Diabetes Risk

Lipitor, also sold under the generic name atorvastatin, is one of a class of drugs known as statins used to control cardiovascular conditions and frequently prescribed to lower cholesterol.

Statins are some of the most widely prescribed of all medicines. By the last quarter of 2014, atorvastatin had become the fourth most widely used therapeutic drug in the U.S., with 22 million outpatient prescriptions on record.

Lipitor’s clinical efficacy has been most clearly established when it’s used to treat cardiovascular conditions in high-risk men, reducing their instance of cardiovascular events by 36 percent according to one study.

However, reexamination of data from clinical trials revealed a nine percent increase in the risk of diabetes related to Lipitor treatment. Further, these results came from trials that studied mostly men: some studies’ population of subjects was as much as 80 percent male. Studies that focused specifically on women found a much higher increase of 48 percent.

The Quarter Watch report says that in 2014 Lipitor was the most frequent subject of litigation-based adverse event reports collected by the FDA, with 4,727 such Lipitor lawsuits reported.

All of these cases involved type-2 diabetes, and 98 percent of them were brought by women. Some cases also implicated kidney disease, vision conditions, and nerve damage as complications of diabetes.

The ISMP report notes that Lipitor’s balance of efficacy with safety is called into question when it apparently increases the risk of diabetes by two to three times for women, who are less at risk for cardiovascular conditions than men.

Lipitor Lawsuits

The relationship between Lipitor and diabetes is at the heart of the current wave of Lipitor lawsuits. Generally, plaintiffs allege that manufacturer Pfizer knew or should have known that Lipitor was linked to a significant increase in the risk of type-2 diabetes in women, yet failed to properly warn physicians and patients about that risk.

In February 2012, the FDA required Pfizer to add to Lipitor’s labeling a mention of the drug’s effect on blood sugar levels. That notation is still on the label today.

Both plaintiffs in the Lipitor lawsuits and some critics in the medical field say that this warning may not be strong enough. Plaintiffs further argue that this lack of a more assertive warning makes Lipitor defective and unsafe.

Over 2,500 of these Lipitor lawsuits have been consolidated into a single multidistrict litigation now going on in the U.S. District Court for the District of South Carolina. Trials in the Lipitor MDL are scheduled to begin in November.