People who were vaccinated with Johnson & Johnson's COVID-19 shot could benefit from a booster made by Moderna or Pfizer, according to a study published Oct. 13 in preprint server MedRxiv.
The National Institutes of Health study on mixing COVID-19 vaccine doses, which has yet to be peer reviewed, included 458 people. Participants received an extra shot made by either the drugmaker that manufactured their original vaccine or a different drugmaker. Their antibody levels were measured two weeks and four weeks after they received the boosters.
All the combinations made participants' antibody levels higher. However, participants who received an extra dose made by Pfizer or Moderna had higher increases in their antibody levels than those who received an extra dose made by Johnson & Johnson.
Participants who originally were vaccinated with a Johnson & Johnson shot and received a Moderna booster saw their antibody levels rise 76 times higher within 15 days. Those who received aPfizer booster saw their antibody levels rise 35 times higher, and those who were administered another Johnson & Johnson shot saw their antibody levels rise four times higher.