The U.S. Food and Drug Administration is discussing a move to administer Moderna coronavirus vaccines in half-doses to distribute the jab wider across the population, according to a top official with Operation Warp Speed (OWS).
The comments from Dr. Moncef Slaoui, the chief operating officer for OWS, arose Sunday as he told CBS’ Margaret Brennan that halving the dose volume in vaccines administered to those aged 18 to 55 translates to an “identical immune response” to the full, 100-microgram dose.
This plan would inoculate twice the amount of people, Slaoui said, calling it a “more responsible approach based on facts and data.”
“We are in discussion with Moderna and with the FDA, of course ultimately it will be an FDA decision to accelerate injecting half the volume,” he continued.
Slaoui’s comments surfaced after he was pressed to detail how the federal government is taking action to help states actually administer doses into Americans’ arms, a slow effort plagued with logistical hurdles like strained staffing and funding.
A former FDA head later agreed that tweaking the dosing would speed up vaccination efforts.
“They may move to that,” former FDA commissioner Dr. Scott Gottlieb told CNBC co-hosts Monday, speaking about halving Moderna dose volumes. “That would certainly extend the supply.”
By Monday morning, the federal government had distributed at least 13 million doses, and over 4.2 million vaccines have gone into Americans’ arms, according to figures from the Centers for Disease Control and Prevention. Officials have said there are likely lags in reporting, however.
While U.K. officials are backing a decision to space out inoculations by 12 weeks between the first and second dose, Slaoui, and Dr. Anthony Fauci, the nation’s leading infectious disease expert, have dismissed this approach.
“I think it’s not reasonable, when vaccines have been developed with two doses given 21 days apart, or 28 days apart and where we have the data on their safety and their efficacy,” Slaoui said. “We have no data on one dose if we leave people a month, two months, three months with maybe incomplete immunity, waning immunity, maybe even the wrong kind of immune response induced that is then corrected by a second dose.”
While Americans appear to be gaining trust in the vaccine, tampering with the process may threaten to undo newly gained trust.