COVID-19 ‘Mix and Match’ Vaccines to Undergo Clinical Tests


COVID-19 ‘Mix and Match’ Vaccines to Undergo Clinical Tests

The National Institutes of Health announced Tuesday that it has begun a clinical trial observing the effects of adults who are fully vaccinated with one COVID-19 vaccine regimen receiving a booster shot of another regimen.

The trial will include 150 adults who will receive a single booster dose of the Moderna COVID-19 vaccine 12 to 20 weeks after they have received a full regimen of the Johnson & Johnson, Moderna, and Pfizer vaccines.

Additionally, people who have not received a COVID-19 vaccine authorized by the Food and Drug Administration will be able to participate in the trial and will receive the two-dose Moderna vaccine regimen and a booster 12 to 20 weeks later.

Each vaccine group will include 25 people aged 18-55 and 25 people aged 56 and older.

“Although the vaccines currently authorized by the U.S. Food and Drug Administration offer strong protection against COVID-19, we need to prepare for the possibility of needing booster shots to counter waning immunity and to keep pace with the evolving virus,” said Dr. Anthony Fauci, director of the National Institute for Allergy and Infectious Diseases. “The results of this trial are intended to inform public health policy decisions on the potential use of mixed vaccine schedules should booster doses be indicated.”

Participants in the study will be asked to complete telephone check-ins and in-person follow-ups as well as provide blood samples for one year after the study.

The three major U.S. vaccine manufacturers have indicated people who have received a full vaccine regimen should expect to require a booster within a year of their final dose.

Pfizer in April said it was likely a third dose would be required somewhere between six and 12 months after completing the first two-shot regimen and from there vaccinations would take place annually.

Moderna said its vaccine provides protection for six months and that it is developing a booster, and Johnson and Johnson said its single-shot vaccine will likely need to be given annually.