Pfizer-BioNTech Covid-19 vaccines at a retirement home in Worcester, Pennsylvania, United States, Wednesday, August 25, 2021.
Hannah Beier | Bloomberg | Getty Images
Recipients of the Johnson & Johnson Covid-19 vaccine would be better off getting vaccinated by Pfizer or Moderna, a much-anticipated US study suggested on Wednesday.
The National Institutes of Health study of the “mix and match” of Covid vaccines involved more than 450 adults who have received one of the three regimens currently available in the United States: J&J, Moderna or Pfizer. The study, which examines whether there are pros or cons of using different boosters, has yet to be peer reviewed.
The volunteers were divided into groups and received an additional injection of their original vaccine or a booster from another company. Antibody levels were measured two weeks and four weeks after the boosters were given.
All of the combinations increased antibody levels, although boosters from Pfizer and Moderna seemed to work the best. People who received a booster dose of Moderna or Pfizer vaccines had a four-fold increase in their antibody 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 exchange third doses; the results were about the same. The volunteers who initially received the J&J vaccine appear to have obtained a better immune response if they received a booster made by Pfizer or Moderna.
“These data suggest that if a vaccine is approved or authorized as a booster, an immune response will be generated regardless of the primary Covid-19 vaccination schedule,” the researchers wrote in the study. “Heterologous primary stimulation strategies may offer immunological advantages to optimize the extent and longevity of protection obtained with currently available vaccines,” they added.
J & J’s single-dose vaccine uses adenovirus, while Pfizer and Moderna’s two-dose vaccines use mRNA technology. The idea of some scientists is that by “mixing and matching” vaccines that use different platforms, people might be able to achieve broader protection against the coronavirus and its newer variants.
The results released Wednesday are expected to be presented on Friday at a key meeting of the Food and Drug Administration’s vaccine advisory committee.
This is a developing story. Please check for updates.