(Reuters) - The U.S. Food and Drug Administration chief on Thursday defended a plan to administer Bavarian Nordic's monkeypox shot intradermally after the company raised doubts about the safety of the method, citing a lack of data.
The company had on Tuesday said there was some evidence that a shot of Jynneos between the layers of the skin could result in increased reactions compared to the approved method of injecting it underneath the skin.
FDA chief Robert Califf, however, backed the method saying while the intradermal administration led to some mild-to-moderate side effects, it produced a similar immune response to injecting the vaccine below the skin.
"In authorizing an unapproved use of an already approved product, the FDA is ensuring the vaccine meets high standards for safety, immune response and manufacturing quality," Califf tweeted. (https://
The U.S. health regulators had on Monday authorized the emergency use of the shot by recommending an alternate method of use, which would result in splitting a single vial of Jynneos into five doses.
"This may have a negative impact on vaccine uptake and coverage," the company had said in a letter to the FDA on Tuesday.
The company is also testing the potency of doses that the government had bought earlier and is stored in the Strategic National Stockpile to see if they can be used to fight the current outbreak.