When the labeling change was released in 2012, a top FDA official underscored that the agency still stood behind the drugs: "Clearly, we think that the heart benefit of statins outweighs this small increased risk (for diabetes)," Amy Egan, a deputy director for safety at the agency's Division of Metabolism and Endocrinology, said in a statement at the time.
Statins are a class of drugs that block the liver's production of cholesterol to reduce the risk of heart disease. Type 2 diabetes, once known as adult-onset or noninsulin-dependent diabetes, is a chronic condition that affects the way the body metabolizes glucose.
The recent spike in lawsuits followed a decision by a federal judicial panel to consolidate all Lipitor diabetes lawsuits from around the country into a single Federal courtroom in Charleston, South Carolina. Pfizer opposed the consolidation, arguing it would prompt copycat filings. The first case is scheduled to be tried next July.
Pfizer said in a statement that it denied liability and would fight the lawsuits.
It is not uncommon for a drugmaker to get hit with thousands of lawsuits over its products after the FDA orders a label change alerting users to newly found risks. Takeda Pharmaceutical, for instance, is facing more than 3,500 federal lawsuits since 2011 when the FDA ordered it to update the label on its diabetes drug Actos to warn about bladder cancer. Takeda has denied liability.
But several factors set the Lipitor diabetes cases apart from those against other drug companies. For one, Lipitor is the best-selling prescription drug of all time, racking up global sales of more than $130 billion since it went on the market in 1996. More than 29 million patients in the United States have been prescribed the drug, suggesting there is a vast pool of potential plaintiffs.
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On the other hand, potentially complicating matters for plaintiffs, the FDA emphasized the benefits of statins even as it warned of the risks.
When the labeling change was released in 2012, a top FDA official underscored that the agency still stood behind the drugs: "Clearly, we think that the heart benefit of statins outweighs this small increased risk (for diabetes)," Amy Egan, a deputy director for safety at the agency's Division of Metabolism and Endocrinology, said in a statement at the time.
Statins are a class of drugs that block the liver's production of cholesterol to reduce the risk of heart disease. Type 2 diabetes, once known as adult-onset or noninsulin-dependent diabetes, is a chronic condition that affects the way the body metabolizes glucose.
Risks and benefits
The seemingly mixed message from the FDA suggests that litigation will focus on two questions: how big a diabetes risk do women using Lipitor face, and whether that risk is mitigated by the drug's cardiovascular benefits.
H. Blair Hahn of Mount Pleasant, South Carolina, the lead lawyer appointed to represent Lipitor plaintiffs in federal court, said the plaintiffs contracted diabetes as a consequence of taking Lipitor, and that women with diabetes see the length and quality of their lives reduced.