People receiving Johnson & Johnson’s COVID-19 vaccine may benefit from a booster dose from Pfizer or Moderna, preliminary results from a US study published Wednesday showed.
The study, funded by the National Institutes of Health (NIH), was eagerly awaited in the United States because it looked at the possibility of “mixing” vaccines—a different vaccine than the initial dose for a booster shot. Using – which is currently not allowed in the country.
The study was conducted on 458 adults who were vaccinated with one of three US-approved brands (Pfizer, Moderna or J&J) for at least 12 weeks.
These three groups were split into three new groups to receive one of the vaccines available as a booster. The nine groups each consisted of about 50 people.
The researchers analyzed antibody levels 15 days after the booster shot.
For people originally infected with J&J, antibody levels were four times higher after a J&J booster, 35 times higher after a Pfizer booster, and 76 times higher after a Moderna booster.
The study noted that those who had originally received the Moderna shots had higher antibody levels “despite the booster vaccine being administered,” when compared to those who had initially received Pfizer or J&J.
Additionally, “no safety concerns were identified” after the booster dose was given, it found.
The study, which has not yet been peer reviewed, has several limitations, however.
The number of participants was small, and immune responses may have developed over time, beyond the 15 days observed during the study.
“The important thing is not to get too carried away with the findings,” tweeted Baylor College of Medicine professor Peter Hotez.
He said the results of tests on a second J&J booster shot conducted by the company were “impressive.”
The NIH study should prompt discussion by a US Food and Drug Administration (FDA) expert committee, which is scheduled to consider applications for booster doses from Moderna and J&J on Thursday and Friday, respectively.
A booster from Pfizer has already been approved in the United States for certain populations, such as people 65 years of age or older, adults with high-risk medical conditions, and those in jobs where they are frequently exposed to the coronavirus. come.
(Except for the title, this story has not been edited by NDTV staff and is published from a syndicated feed.)