This week, federal regulators are anticipated to approve the mixing and matching of COVID-19 booster doses to provide flexibility as the extra injection campaign grows.
The Food and Drug Administration is expected to announce the approval of booster doses for the Moderna and Johnson & Johnson vaccines soon, following the approval of a third dose for the Pfizer vaccine for many Americans last month.
A US health official familiar with the subject who was not authorized to talk publicly before the announcement previewed the move on Tuesday.
https://youtu.be/ib5VP0X-yHA
The FDA was expected to suggest that using the same brand for a booster was still recommended, especially for Pfizer and Moderna's coronavirus vaccines, which have proven to be the most effective. The CDC was still working on advice for the J&J single-shot vaccination.
According to preliminary findings from a government study of several booster combinations, an extra dose of any type boosts levels of virus-fighting antibodies, independent of the brand they received initially. However, users of the single-dose J&J vaccine had the most significant response, with antibody levels rising 76-fold and 35-fold after either a Moderna or Pfizer booster, respectively, compared to a four-fold rise after a second J&J shot.
One perplexing option is which Moderna dosage to use in conjunction with other brands. Moderna has requested that its booster be half the initial amount, claiming that it is sufficient for patients who have received two doses. However, the mix-and-match trial employed full-strength extra doses, and there's no way to tell if a half-dose would be as effective.
