Federal officials are hoping that encouraging new findings will spur more Americans to get an updated booster before a feared surge in coronavirus cases this winter.
A new study by Pfizer and BioNTech suggests that their updated coronavirus booster is better than its predecessor at increasing the antibody levels of people over age 55 against the most common version of the virus now circulating.
Federal officials are hoping that the encouraging results will improve what has so far been a dismal public response to the retooled shots. Only about 8 percent of Americans ages 5 and up have received the new boosters from Pfizer and Moderna since they were introduced in September.
Pfizer and BioNTech announced the study results in a news release on Friday. The companies said that one month after getting the new booster, clinical trial participants over 55 had antibody levels that were about four times as high as those who received the original booster. The study measured the levels of neutralizing antibodies against two sister subvariants of Omicron known as BA.4 and BA.5.
The number of participants in the study was small, with 36 people over 55 receiving the new booster and 40 people in that age group receiving the old one. And because the study measured antibody levels only a month after trial participants were boosted, it did not provide any indication about the potential durability of the protection in the longer term.