FDA questions Teva drug's impact on Parkinson's
By MATTHEW PERRONE - AP Health Writer | AP – 15 hours
..WASHINGTON (AP) — Studies of Teva Pharmaceuticals' drug Azilect for Parkinson's disease failed to convince federal scientists that the pill slows the progression of the disease, suggesting the government will reject the company's bid for expanded use of the drug.
Reviewers for the Food and Drug Administration said Thursday that the company's research paints a mixed picture of the drug's effectiveness. Azilect, known generically as rasagiline, is already approved to treat symptoms of Parkinson's, a debilitating disease that slowly breaks down brain cells that control movement.
But Teva has asked the FDA to expand approval so that it can be prescribed to slow the underlying disease. Currently no treatments are approved for that indication.
In briefing documents posted online, the FDA pointed to a number of issues in Teva's studies, including widely disparate results between men and women and varying degrees of symptoms among patients studied.
A 1 milligram dose of the drug appeared to slow patients' disease based on a rating scale that measures symptoms and disease progression, including its effects on mental state, motor skills and daily activities. However, the FDA said a 2 milligram dose of the drug failed to show similar results.
"The failure of the 2 mg group raises serious questions about the interpretation of this study, and, therefore, about whether or not rasagiline has been shown to have disease-modifying effects," FDA reviewers said in documents posted online. "There is no obvious biological explanation for why the 2 mg dose should not be disease-modifying, if the 1 mg dose is."
FDA staff also acknowledged there are no firm criteria for measuring a drug's ability to slow Parkinson's disease.
Teva studied its drug in 1,176 patients with very early Parkinson's disease, who had not been treated previously.
On Monday, the FDA will ask a panel of outside experts whether Teva has provided convincing evidence that its drug impacts the course of Parkinson's disease. The agency is not required to follow the group's advice, though it often does.
About 5 million people worldwide, and 1.5 million in the U.S., have Parkinson's, characterized by increasingly severe tremors and periodically stiff or frozen limbs. Patients gradually lose brain cells that produce dopamine, a chemical key to the circuitry that controls muscle movement. There is no cure, although dopamine-boosting medication and an implanted device called deep brain stimulation can help some symptoms.
The cause of the disease is unknown.
The U.S.-traded shares of Israel-based Teva Pharmaceutical Industries Inc. dipped 1 cent to $39.02 in afternoon trading.