The National Institutes of Health (NIH) in the U.S. has launched a clinical trial involving people who received the Pfizer or Johnson & Johnson COVID-19 vaccines, administering a booster shot of the Moderna vaccine to determine whether mixing vaccines offers greater protection. This study, led by the NIH, aims to evaluate the effectiveness of combining COVID-19 vaccines, as reported by the British newspaper "Daily Mail."
A total of 150 fully vaccinated participants who received the Pfizer or Johnson & Johnson vaccines will be given a booster shot of the Moderna vaccine. Some participants who initially received two doses of Moderna will also receive the same booster. It is noted that boosters may be necessary to combat various evolving variants of the virus, which are more transmissible.
Researchers hope to identify which vaccine combination is the most effective against the variants. Initial results from the study are expected to be available by late summer 2021. Currently, vaccine manufacturers are working on developing booster doses to protect against the more infectious and contagious variants.
NIH researchers want to ascertain whether mixing vaccines is safe and test the theory that combining different vaccines could potentially enhance immunity against COVID-19. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, who is leading and funding the study in the U.S., stated that while the currently authorized vaccines provide strong protection against COVID-19, "we need to be prepared for the possibility of needing booster doses to address waning immunity and keep pace with the evolving virus."
The results of this trial aim to inform public health policy decisions regarding the potential use of mixed vaccine schedules if booster doses are indicated. The newspaper explained that data will be collected over the next year, assessing participants' safety against the virus and whether there are any unique side effects from mixing vaccines.
There will also be a separate group of unvaccinated individuals receiving two doses of the Moderna vaccine, followed by a third shot anywhere from 12 to 20 weeks later. Additionally, study members who contract COVID-19 will be tested to determine if they have contracted one of the virus's variants, with the goal of identifying the most effective vaccine combination against the numerous variants.
The study was announced amid claims that Americans may soon need another booster dose of the COVID-19 vaccine to remain protected from the virus. Early clinical trials suggest that a third dose may be needed as early as September for those vaccinated early on. It is likely that booster doses will be required due to the many variants of the virus circulating worldwide. Currently, over 60% of American adults have received at least one dose of the COVID-19 vaccine.
