"As with the manufacturing of any complex biologic medication or vaccine, the start-up for a new process includes test runs and quality checks to ensure manufacturing is validated and the end product meets our high-quality standards", the company said on Wednesday, adding that "This quality control process identified one batch of drug substance that did not meet quality standards at Emergent Biosolutions".
"This batch was never advanced to the filling and finishing stages of our manufacturing process", Johnson & Johnson specified.
According to The New York Times, the ingredients of two coronavirus vaccines were accidentally mixed up by Emergent employees several weeks ago, and up to 15 million doses of the Johnson & Johnson vaccine were thus ruined.
Johnson & Johnson is now waiting for FDA authorisation for the Baltimore facility. While the FDA investigates the incident at the plant, future shipments of the company's vaccines in the US might be delayed.
Johnson & Johnson's single-shot coronavirus vaccine was approved for emergency use in the US at the end of February, becoming the third vaccine to be authorised by the FDA (in addition to the Pfizer/BioNTech and Moderna COVID-19 vaccines).