Up to 15M Johnson & Johnson coronavirus vaccine doses ruined due to human error: NYT

Johnson & Johnson's COVID-19 vaccine rollout has been slower than expected in the U.S., with just 6.8 million doses delivered to states in the first month. Now, The New York Times has revealed behind-the-scenes details into an unfortunate mix-up in the production process.

Workers at an Emergent BioSolutions plant in Baltimore mixed up vaccine ingredients weeks ago and ruined a large batch of the vaccine containing up to 15 million doses, the NYT reports. The FDA is investigating the mistake, but the episode has led to a temporary halt of future J&J shot deliveries from the site, according to the newspaper. In a statement, J&J said it's working with federal authorities to deliver 24 million doses of the vaccine in April.

The mistake happened early in the production process, so none of the doses made it out to distribution.

Federal investigators have ruled that the episode was the result of "human error," NYT reports.

Moving forward, J&J is moving to implement tighter controls at its manufacturing partner, the company's statement said. J&J and AstraZeneca, another leading COVID-19 vaccine player, tapped the contract manufacturer in their production ramp-up efforts last year.

J&J has met its goal to ship 20 million doses to the U.S. government by the end of March, the company said in its statement. Centers for Disease Control and Prevention (CDC) data show that just 6.8 million doses have been delivered to states, and 3.3 million doses have been administered.

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The company said its manufacturing ramp-up "includes test runs and quality checks to ensure manufacturing is validated and the end product meets our high-quality standards." That process identified a batch that didn't meet standards at the Emergent site, which J&J noted has not yet been authorized.

Emergent spotted the issue and notified the FDA, J&J said.

Moving forward, as the company and Emergent seek an FDA manufacturing authorization for the site, J&J is "providing additional experts in manufacturing, technical operations and quality to be on-site at Emergent to supervise, direct and support all manufacturing of the Johnson & Johnson COVID-19 vaccine."

Working with officials at the Department of Health and Human Services, the company plans to ship 24 million doses of the vaccine in April, the statement said. J&J has leaned on its vaccine plant in the Netherlands to help with production while its U.S. supply chain comes online. For the first half of the year, J&J is aiming to deliver 100 million doses to the U.S.

A representative from Emergent didn't immediately respond to a request for comment.

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When J&J executives spoke with the investment community about the scale-up on the company's fourth-quarter earnings call in late January, executives didn't raise any concerns about the company's ability to meet supply commitments. Chief Financial Officer Joe Wolk said the company was "very comfortable" fulfilling the orders it had booked but that there could be "fluidity" around timing.