FDA investigators indicate that a Pfizer subsidiary shipped contaminated batches of Torisel, a kidney cancer drug, to the United States and took months to warn the agency.
According to a warning letter sent to Pfizer over its Wyeth Lederle plant in Catania, Italy late last month, there were a number of quality control isssues with Torisel, and the company’s failed to adequately to warn the FDA that there was a problem for months.
The FDA indicates that on April 17, 2012, the manufacturing plant detected endotoxin results that were out of specification, suggesting bacterial contamination of a batch of Torisel. However, some of that same batch had already been shipped to the U.S. on January 5, 2012. According to the warning letter, Pfizer waited until August before informing the FDA that contaminated drugs had been sent to U.S. customers.
In addition to not telling the FDA about the problem, Pfizer also failed to adequately follow up to determine what the problem was. The warning letter notes that while they tested several samples and even sent one sample to an outside testing facility, the results were inconsistent, which should have triggered further action on the part of the company.
“Your investigation into the Torisel Diluent batch AGMV/1 failures began on April 17, 2012, and you continued to test and re-test samples from this lot through August 14, 2012,” the warning letter notes. “At no point did you conduct quantitative endotoxin testing to determine the extent of the endotoxin specification failure.”
When Pfizer finally reported the problem, the company claimed that cardboard box debris may have contaminated the samples, and that the company had thought the results that showed contamination were false positives. However the FDA says the company has “proposed no credible explanation” for pieces of cardboard could have gotten into sterile drug samples.
The FDA indicates that the company’s excuse was not probable and that the source of contamination is still unknown. It also pointed out that the company at first did not address the shipment of Torisel sent to the U.S. Those drugs were later recalled.
Pfizer has been directed to take prompt action to address issues at the plant and warned that until action is taken the FDA may withhold approval of new drug applications or supplements. The FDA said it may also bar shipments of drugs from the Italian facility until the problems are fixed.