That brought to 75 million the total number of doses that cannot be used because of concerns about contamination at a southeastern Baltimore plant, operated by Emergent BioSolutions, Johnson & Johnson’s subcontractor and a longtime government contractor.
The vaccine-making factory has been shut for the past two months while regulators determine the cause of contamination that ruined many doses, whether it is safe to reopen the facility, and what to do with the equivalent of at least 170 million doses of vaccine that Emergent produced for Johnson & Johnson and AstraZeneca, another vaccine developer.The F.D.A.’s memo stated that Emergent failed to properly segregate zones in which workers manufactured vaccines developed by Johnson & Johnson and AstraZeneca in order to prevent cross-contamination that could render doses unsafe or ineffective.When Emergent first began producing the Johnson & Johnson vaccine in November, the memo stated, the plant’s workers weighed and readied ingredients used to produce the two vaccines in separate areas.