The recipients were supposed to get their first doses of the Moderna vaccine on Wednesday at a clinic run by the Boone County Health Department, according to a statement from the West Virginia National Guard.

Instead, they were given a Regeneron antibody product, which is used to treat Covid-19.

“The moment that we were notified of what happened, we acted right away to correct it, and we immediately reviewed and strengthened our protocols to enhance our distribution process to prevent this from happening again,” said Maj. Gen. James Hoyer, adjutant general of the West Virginia National Guard, in the statement.