(CNN) The US Food and Drug Administration said Wednesday that new production of Johnson & Johnson's Covid-19 vaccine remains paused at the Emergent BioSolutions facility where millions of potential doses were contaminated, and the agency and the company are working through a list of potential quality issues.
The FDA's inspection of Emergent's Bayview facility in Baltimore ended Tuesday and a newly released document details issues that could affect quality during manufacturing -- including incomplete investigations into cross-contamination, written procedures that weren't followed, poorly maintained facilities and a lack of employee training.
New production was halted at the FDA's request, Dr. Janet Woodcock, acting FDA commissioner, and Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, said in a joint statement released on Wednesday.
"For the vaccines already manufactured, the products will undergo additional testing and will be thoroughly evaluated to ensure their quality before any potential distribution," Woodcock and Marks said. "We will not allow the release of any product until we feel confident that it meets our expectations for quality."
The Emergent plant had been making coronavirus vaccines under contract for both Johnson & Johnson and AstraZeneca. In March, a batch of Johnson & Johnson "drug product" -- which could have made 15 million doses of the vaccine -- failed quality control and was taken out of production.
In the new report, the FDA says Emergent has not thoroughly investigated cross-contamination of a viral vaccine drug substance batch, and there was not a thorough review of how people moved in and around the facility as a potential source of contamination.
"There is no assurance that other batches have not been subject to cross-contamination," the report says.
Based on security camera footage and direct observation, the FDA report says written procedures to prevent cross-contamination aren't followed during production or documented. Components and product containers were not handled or stored in a way to prevent contamination; written procedures to assure drug substances are manufactured at the appropriate quality, strength and purity "are inadequate"; and employees weren't properly trained.
The building used to manufacture the vaccine drug substance wasn't a suitable size or design to facilitate cleaning and proper operations, and equipment used "is not of adequate size" to operate as intended, the report says.
Additionally, the FDA's inspection document notes peeling paint, unsealed bags of medical waste, residue on walls and damaged floors and rough surfaces that "do not allow for adequate cleaning and sanitization."
In a statement, Emergent said it is "committed to working with the FDA and Johnson & Johnson to quickly resolve the issues identified."
There have already been changes to reduce risk of contamination at the Baltimore plant.
Early this month, the federal government told AstraZeneca it must move its vaccine production elsewhere. The AstraZeneca Covid-19 vaccine is not yet authorized for emergency use in the United States.
Johnson & Johnson was also told to fully take over production of the vaccine at the Emergent plant. The independent manufacturing company does not yet have FDA authorization to manufacture or distribute any of Johnson & Johnson's vaccine or components and no vaccine manufactured at the plant has been distributed for use in the United States.
On Wednesday, Johnson & Johnson said it will "redouble" efforts to secure an emergency use authorization for the Covid-19 vaccine drug substance manufactured at Emergent's Bayview campus.
"Johnson & Johnson will exercise its oversight authority to ensure that all of FDA's observations are addressed promptly and comprehensively," the company statement noted on Wednesday.
In the meantime, Johnson & Johnson said it has increased the number of manufacturing sites to 10, in addition to its internal manufacturing site in the Netherlands.
"We are working around the clock to develop and broadly activate our manufacturing capabilities to supply our COVID-19 vaccine worldwide, and we appreciate the ongoing and extensive collaborations and partnerships we have with governments, health authorities and other companies to help end this pandemic," it said.
The actions around Emergent aren't related to the pause on the use of the Johnson & Johnson shot in the United States.
Nearly 8 million people in the United States have been vaccinated with the Johnson & Johnson Covid-19 vaccine, but administration was halted after the US Centers for Disease Control and Prevention and FDA identified six cases of rare, severe blood clots among people who received it.
Emergent's situation likely won't influence or push back any decisions around possibly resuming Johnson & Johnson vaccinations moving forward, Dr. Anthony Fauci, chief medical adviser to President Biden, told CNN's Victor Blackwell on Wednesday.
"I don't think that's going to be a factor in whether or not the CDC and the Advisory Committee on Immunization Practices, and ultimately the FDA, will make a decision," said Fauci, director of the National Institute on Allergy and Infectious Diseases.
"The decision of what to do with this vaccine as a vaccine product is not going to be influenced by that. It's going to be influenced by the data and safety -- not in what's going on there," Fauci said. "But you can be assured, and the American public can be assured, that no vaccines are going to go out of there unless the FDA is quite confident in them."