Production of the British-Swedish drug maker AstraZeneca’s Covid-19 vaccine was stopped at a factory in the US after a mix-up by a subcontractor contaminated millions of doses.
Johnson & Johnson said it would take over the running of the Emergent BioSolutions plant in Baltimore, Maryland.
A subcontractor at the factory added ingredients used by AstraZeneca to those in Johnson & Johnson's shots, spoiling 15 million of the latter's doses.
The error was spotted during quality control checks before the vaccines went to the fill-and-finish stage.
The US government ordered AstraZeneca to produce its vaccine at a different plant to that of Johnson & Johnson, to prevent similar mistakes, the New York Times reported.
It is the latest setback for AstraZeneca after the company was criticised by the US government for using outdated data in vaccine trial results.
Several countries, including Canada, France and Germany, limited use of its vaccine after blood clots were reported in a handful of people who received it.
The incidence was extremely rare and there was no evidence to suggest the clots were caused by the shot. Millions of people have been inoculated with the drug worldwide with no adverse effects.
AstraZeneca, whose vaccine has not been approved in the US, said it would work with President Joe Biden’s administration to find a new production site.
US infectious disease expert Dr Anthony Fauci told Reuters the country might not need AstraZeneca’s vaccine even if it gains approval.
Washington has agreed to send Mexico and Canada about four million doses of the shot.
Emergent said the Department of Health and Human Services increased its order by $23 million to expand vaccine production in Baltimore.
“The $23m will be used for the purchase of biologics manufacturing equipment specific to Johnson & Johnson’s Covid-19 vaccine for the potential expansion of manufacturing of that bulk drug substance into a third suite of Emergent’s Baltimore Bayview facility,” the company said.
Johnson & Johnson restated its promise to deliver 100 million doses to the US government by the end of May.
