Allergan Inc.'s Irish manufacturing facility for Botox, the botulinum toxin used as a muscle relaxant, doesn't meet sanitation requirements designed to prevent contamination, the U.S. Food and Drug Administration said in a warning letter.
The agency said the violations of U.S. manufacturing practices were uncovered during a July inspection of the facility in County Mayo, Ireland. The letter, dated Oct. 6, was released Tuesday.
Shares of Irvine-based Allergan, the second-largest manufacturer of eye-care products after Bausch & Lomb Inc., fell $5.13 to $57.25.
"As far as we understand, it's already been worked out" with the FDA, said Ira Haskell, director of corporate communications at Allergan.
The company is preparing a written response to the agency's letter to explain the corrective measures Allergan has begun, he said.
The FDA letter said the facility failed to fully investigate contamination of its sterile areas, to have written procedures to detect problems, to properly clean and disinfect systems and to monitor the finished products for proper strength, purity and quality.
In addition, samples of the drugs weren't evaluated annually to make sure they hadn't deteriorated, and the facility stored information about Botox in areas where unauthorized personnel could get access to it, the agency said.
The FDA said it received Allergan's written response to some of the plant's shortcomings in August, although it had additional questions and comments about planned corrections.
Allergan sells Botox in the U.S. for eye muscle disorders and elsewhere for a range of neuromuscular conditions. It's one of the company's fastest-growing products, and Allergan is studying its use for easing the spasticity that often accompanies stroke.
The company agreed to pay $824,000 in January to settle U.S. government claims that it was exporting Botox to Iran and other countries where it could be used in biological warfare. The company said Botox couldn't be used as a weapon, even though the active ingredient can be poisonous in its natural, unpurified form.
The FDA sends hundreds of warning letters to companies each year, and only a small minority of them result in significant agency action.