Moderna CEO warns people may need a fourth Covid shot as the efficacy of boosters is likely to decline over time

January 10, 2022: On Thursday, Moderna CEO Stephane Bancel said the efficacy of boosters against Covid-19 would likely decline over time, and people may need a fourth shot in the fall to increase their protection.

Bancel said people who received their boosters last fall would likely have enough protection to get them through the winter when new infections surge as people gather indoors to escape the cold.

However, Bancel said the efficacy of boosters would probably decline over several months, similar to what happened with the first two doses. Goldman Sachs interviewed the Moderna chief during the investment bank’s healthcare CEO conference.

The Moderna CEO said governments, which include the U.K. and South Korea, are already ordering the doses in preparation. “I still believe we’re going to need boosters in the fall of ’22 and forward,” Bancel said, which added that people who are older or have underlying health conditions might need annual boosters for years to come.

“We have been saying that we believe first this virus is not going away,” Bancel said. “We’re going to have to live with it.”

Moderna published preliminary data in the previous month that showed its currently authorized 50 microgram booster shot surged the antibodies that block infection from omicron 37-fold. A 100 microgram booster increased those antibodies 83-fold.

Booster shots play an increasingly important role in public health strategies to control the virus, with protection from the original two photos that have taken a significant blow from omicron.

Data from the U.K. found that Moderna and Pfizer’s two-dose vaccines are only nearly 10% effective at preventing symptomatic infection from omicron 20 weeks after the second dose.

A similar study, published by the U.K. Health Security Agency found that booster doses are up to 75% effective to prevent symptomatic infection two weeks after receiving the shot.

Although, the efficacy of booster shots starts to decline after about four weeks, according to the study. Boosters are 55% to 70% effective at preventing infection at weeks five to nine and 40% to 50% effective ten weeks after receiving the shot.

Last month, Pfizer CEO Albert Bourla told CNBC that people would likely need a fourth dose, and the shot may be required sooner than expected due to omicron’s virulence.