MedImmune Inc. failed to address multiple problems - including bacterial contamination - identified last year at a FluMist manufacturing plant in Europe, "substantially increas[ing] the risk of product failures" in batches of its nasally inhaled influenza vaccine, according to a warning letter released by the U.S. Food and Drug Administration yesterday.
Last week, the Gaithersburg biotechnology company said the federal agency was withholding approval of its application to expand FluMist's use to include most children younger than age 5 until the concerns are resolved.
"We're working to address the issues and actively cooperating with the FDA," MedImmune spokeswoman Jamie P. Lacey said yesterday.
Even though it's the company's best-known product, FluMist and its lagging sales have been a chronic disappointment for investors in MedImmune, which agreed last month to be acquired by pharmaceutical giant AstraZeneca PLC for $15.6 billion.
Currently, only healthy people between ages 5 and 49 can take the vaccine, though groups both older and younger are the ones most at risk from flu complications.
This month, an FDA advisory committee recommended that the vaccine's use be widened to children between ages 1 and 5 with no history of wheezing, and to children ages 2 and older regardless of wheezing. MedImmune had expected the agency to grant approval of such use Friday.
Instead, it was told approval was being withheld.
FDA spokeswoman Karen Riley confirmed yesterday that the action was linked to the problems at the United Kingdom manufacturing plant, though approval could be granted before they're all fixed if the company presents a viable plan.
"They at least have to have a plan; they have to have a plan in place," Riley said, noting that problems had been identified last year and this year.
MedImmune plans to manufacture 7 million doses of FluMist for the 2007-2008 flu season and expects to be able to administer the drug to the very young this year, Lacey said. She declined to detail the number of children who might be eligible to take the vaccine if its age indication is expanded, however, and wouldn't discuss how it could affect the vaccine's bottom line.
The FDA's warning letter, sent to MedImmune Chief Executive Officer David M. Mott last week, said agency inspectors found "significant deviations from current good manufacturing practice" at the U.K. plant during an inspection in late March:
Five batches of an ingredient used to make FluMist hadn't been properly filtered of organisms such as bacteria and mold at an expected point.
The company failed to adequately investigate contamination causes or take corrective action.
Cleaning and decontamination processes were deficient. Microorganisms including E. coli and a bacterium typically found in the gastrointestinal tract of mammals were found on an employee's hands, for example.
MedImmune used disinfectants that were banned by the European Union early this year.
The FDA letter acknowledged that these deviations from accepted manufacturing process didn't "necessarily mean that product should be rejected." An accompanying question-and-answer section posted online also said companies can often continue manufacturing while they address plant issues.
It's unclear whether AstraZeneca knew of the plant's issues and their potential effect on administering FluMist to a wider patient population.
Lacey declined to comment on the topic specifically, saying only that MedImmune provided AstraZeneca with information from across the company during a "due diligence" process associated with the acquisition.
AstraZeneca spokeswoman Laura King said she wasn't sure if her company was informed. She called FluMist a "key" asset, but added that the plant problems, FDA's warning letter and the delayed patient expansion did not change AstraZeneca's "intentions toward MedImmune."
When the British company announced plans to purchase MedImmune, its executives promoted the fact that the move would bring vaccines to their product portfolio for the first time.
MedImmune has 15 days to respond to the FDA's May 24 letter.
The company's stock closed up 37 cents yesterday to $57.73 on the Nasdaq.