Pfizer tweaking COVID-vaccine to protect public from omicron variant

Experts expect surge in fall and winter
Posted at 8:56 AM, Jun 27, 2022
and last updated 2022-06-27 09:56:44-04

NASHVILLE, Tenn. (WTVF) — Every single day scientists are in the lab trying to keep people protected from COVID-19.

Now, Pfizer has tweaked its vaccine to better target the omicron variant. Officials said it's safe and it works.

The vaccines currently used in the U.S. still offer strong protection against severe COVID-19 disease and death -- especially if people have gotten a booster dose. But those vaccines target the original coronavirus strain and their effectiveness against any infection dropped markedly when the super-contagious omicron mutant emerged.

Now with omicron's even more transmissible relatives spreading widely, the Food and Drug Administration is considering ordering a recipe change for the vaccines made by both Pfizer and rival Moderna in hopes that modified boosters could better protect against another COVID-19 surge expected this fall and winter.

Pfizer studied two different ways of updating their shots -- targeting just omicron, or a combination booster that adds omicron protection to the original vaccine. They also tested whether to keep today's standard dosage -- 30 micrograms -- or to double the shots' strength.

In a study of more than 1,200 middle-aged and older adults who'd already had three vaccine doses, Pfizer said both booster approaches spurred a substantial jump in omicron-fighting antibodies.

Pfizer's omicron-only booster sparked the strongest immune response against that variant.

FDA's scientific advisers will publicly debate the data on Tuesday, as they grapple with whether to recommend a change to the vaccines' recipes -- ahead of similar decisions by other countries.