FDA wants to withdraw approval for a drug for low blood pressure

The Food and Drug Administration said Monday that it wants to withdrawal marketing approval for a drug for treating low blood pressure because manufacturers have not been able to provide evidence that it is beneficial. The drug, called midodrine, is sold under the brand name ProAmatine by Shire Development Inc. and is available in generic form from several manufacturers. It is used to treat orthostatic hypotension, in which patients are not able to maintain the correct blood pressure when they stand up, becoming dizzy or faint. An estimated 100,000 Americans took the drug last year, according to the agency.

Midodrine was approved in 1996 under the FDA’s accelerated approval regulations for drugs that treat serious or life-threatening diseases. Such approval requires that the manufacturer submit post-marketing data showing benefit. Shire has not done so, nor have the manufacturers of generic versions.

“We’ve worked with the drug companies to obtain additional information showing the drug’s clinical benefit to patients,” Dr. Norman Stockbridge, director of the FDA’s division of cardiovascular and renal drugs, said in a statement. “Since the companies have not been able to provide evidence to confirm the drug’s benefit, the FDA is pursuing a withdrawl of the product.”

Shire has 15 days to request a hearing on the matter. Generic manufacturers have 30 days. If the agency receives no response, it will revoke approval.

Patients should continue taking the drug and consult their physicians, the agency said.

--Thomas H. Maugh II / Los Angeles Times