All combinations increased antibody levels, although the boosters from Pfizer and Moderna seemed to work the best. People who received a booster dose of Moderna or Pfizer vaccines had a higher increase in their antibiotic responses more often than those who received an extra dose of J&J, according to the study.
The study showed that recipients of the original Moderna or Pfizer vaccines could easily switch third doses; the resultswere pretty much the same. Volunteers who initially received the J&J vaccine appear to have had a better immune response if they received a booster made by Pfizer or Moderna.
There were no serious side effects related to the additional injections and no new symptoms appeared after the participants received the booster injections, the researchers said. Two participants vomited after their boosters; one had received Moderna and the other J&J. Two other people who received a J&J booster reported fatigue or insomnia.
"These data suggest that if a vaccine is approved or cleared as a booster, an immune response will be generated regardless of the primary Covid-19 vaccination pattern, "wrote the researchers in the study." Heterologous primary injection strategies may offer immunologic benefits to optimize the extent and longevity of protection obtained with vaccinescurrently available. "
J & J's single-dose vaccine uses adenovirus, while Pfizer's and Moderna's two-dose vaccines use mRNA technology. Scientists' idea is that by "mixing and matching " vaccines using different platforms, people might be able to achieve broader protection against the coronavirus and its newer variants.
L 'study is likely to fuel a debate about whether to give extra doses to the millions of Americans who have received J & J's vaccines.
Unlike two-shot mRNA vaccines Pfizer and Moderna, J&J hoped to deliver a single shot solution that would protect the public enough to help end the coronavirus pandemic . But its protection, at 72% in the United States, was considered by some to be inferior to Moderna's vaccines andPfizer, both of which have touted efficacy rates above 90%.
A second dose of J&J 's shot results in performance similar to that of mRNA vaccines, increasing the 94% protection against symptomatic infections when given two months after the first dose in the United States, according to company data released on September 21.
In a separate paper released earlier On Wednesday, the FDA said data provided by J&J suggests that recipients may benefit from an additional dose given two months after the first injection.
Regulators wrote that estimates on the Efficacy of J & J's single-injection vaccine in trials and real-world studies "are consistently lower than the highest efficacy estimates for COVID-19 mRNA vaccines.
The results published Wednesday should be presented to a major Food and Drug AdmiAdministration meeting of the Vaccine Advisory Committee on Friday.
Last month, US regulators authorized of the " booster shots of the Covid vaccine developed by Pfizer and BioNTech to "a wide range of Americans, including the elderly, adults with underlying health conditions, and those who work or live in high-risk environments, such as workers health and grocery.