UPDATE 1-U.S. authorizes additional batch of J&J COVID-19 vaccine produced by Emergent

(Adds details on authorization, background, share price)

July 2 (Reuters) - The U.S. Food and Drug Administration said on Friday it had authorized the use of an additional batch of Johnson & Johnson’s one-dose COVID-19 vaccine manufactured at the problem-plagued Baltimore factory of Emergent BioSolutions Inc.

The batch of bulk drug substance - which has not yet been put into vials - can make up to 15 million doses of J&J’s vaccine, according to a source familiar with the matter.

The FDA has now authorized a total of four batches of the vaccine manufactured at the Emergent facility.

“While the FDA is not yet ready to include the Emergent BioSolutions plant ... as an authorized manufacturing facility, the agency continues to work through issues there with Janssen and Emergent BioSolutions management,” the agency said in a statement, referring to J&J’s pharmaceuticals unit.

Production of J&J’s vaccine at the Baltimore site was halted by U.S. authorities in April following the discovery that ingredients from AstraZeneca’s COVID-19 vaccine, also being produced at the plant at the time, contaminated a batch of J&J’s vaccine.

An FDA inspection of the plant also turned up a long list of sanitary problems and bad manufacturing practices.

“As COVID-19 continues to impact countries and cause untold suffering worldwide, we remain committed to producing safe, high-quality vaccines,” J&J said in a statement.

J&J shares closed up about 2% at $168.98.

Reporting by Dania Nadeem in Bengaluru and Michael Erman in New Jersey; Editing by Devika Syamnath and Bill Berkrot