Oct 18, 2021 - Health

COVID vaccine mix-and-matching gains momentum

Anthony Fauci.
Anthony Fauci. Photo: Stefani Reynolds-Pool/Getty Images

The FDA and CDC will likely allow some flexibility for recipients of the Johnson & Johnson COVID-19 to mix and match vaccine boosters, NIAID director Anthony Fauci told ABC News' '"This Week" on Sunday.

Yes, but: The FDA still needs to look at all the data before making a formal authorization, he said.

  • "What likely will happen is that both FDA in their authorization and the CDC will likely give a degree of flexibility based on the individual situations," Fauci said.

Driving the news: NIH data presented on Friday to a key FDA advisory committee showed people who received a shot of J&J's vaccine have a stronger neutralizing antibody response if they receive an mRNA shot instead of a second J&J one.

  • While the committee voted to endorse J&J boosters, they did not yet vote on the "mix-and-match strategy."

What they're saying: "The dogma has always been for other vaccines, you always want to boost with what you’ve primed with. But in this instance, that seems to be different," said board member Archana Chatterjee, who is also dean of the Chicago Medical School.

  • "I'm sold already," said Mark Sawyer, an infectious disease specialist at Rady Children's Hospital. "We need flexibility and improved access."

But, but, but: Advisory board members also identified several data points they're still looking for.

  • For instance, they said, they wanted more data on the longevity of the antibody response.
  • They said they also need to understand what happens to cellular immunity, not just the antibody response, when mixing vaccines.
  • They'd also want to see data on what happens in children when mixing vaccines, as well as better data on underrepresented populations.

The bottom line: While some would like more data, "it does seem there is some consensus this is an important option for people to have," said the FDA's Center for Biologics Evaluation and Research director Peter Marks.

Go deeper: COVID-19 booster shots overtake first doses in the U.S.

Go deeper