With doses at risk of expiration in some states, J&J says it's working to extend the shelf-life of its Covid-19 vaccine

As some US states warn they have Johnson & Johnson COVID-19 vaccine doses that are expiring before they get used, the company and federal officials are looking at whether expiration dates can be extended, reported CNN.

"We're working very hard, both at the federal level and at the local level, to do everything we can to make sure that these vaccines can be used and deployed in the very best possible way," CEO Alex Gorsky said.

Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, stated Wednesday that the FDA is looking into extending expiration dates and how to make use of the doses.

However, it remains unclear how many Johnson & Johnson doses are now at risk of expiring before they're used.

Nearly 11 million doses of the single-dose vaccine -- about half of the 21.4 million doses that have been delivered to states and other jurisdictions -- have not been administered, according to data from the US Centers for Disease Control and Prevention.

"It is an issue that there are expiring doses -- I would imagine in every state," a source familiar with the federal vaccination effort said Wednesday. "However, it's a very small percentage of the overall doses that have been sent to providers -- probably 1-2%."