FDA Greenlights Mixing COVID-19 Boosters and Moderna, J&J Booster Shots

The US Food and Drug Administration (FDA) authorized booster doses of the Moderna and Johnson & Johnson COVID-19 vaccine as well as a “mix and match” approach to boosters for all 3 available COVID-19 vaccines in the indicated populations, the agency announced Wednesday.

“As the pandemic continues to impact the country, science has shown that vaccination continues to be the safest and most effective way to prevent COVID-19, including the most serious consequences of the disease, such as hospitalization and death,” stated acting FDA Commissioner Janet Woodcock, MD, in a press release. “The available data suggest waning immunity in some populations who are fully vaccinated. The availability of these authorized boosters is important for continued protection against COVID-19 disease.”

The FDA amended emergency use authorizations (EUA) for COVID-19 vaccines to allow the following:

• The use of a single booster dose of the Moderna COVID-19 vaccine that may be administered at least 6 months after completion of the primary series to adults aged ≥65 years, 18-64 years at high risk of severe COVID-19, and 18-64 years with frequent institutional or occupational exposure to SARS-CoV-2.
• The use of a single booster dose of the J&J COVID-19 vaccine may be administered at least 2 months after completion of the single-dose primary regimen to adults aged ≥18 years.
• The use of each of the available COVID-19 vaccines as a heterologous—or mix and match—booster dose in eligible persons after completion of primary vaccination with a different available COVID-19 vaccine.
• A single booster dose of the Pfizer-BioNTech COVID-19 vaccine administered at least 6 months after completion of the primary series to adults aged 18-64 years with frequent institutional or occupational exposure to SARS-CoV-2.

The authorizations followed a 2-day meeting last week of the FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC), which unanimously recommended that the FDA authorize booster shots of the Moderna and J&J COVID-19 vaccines in eligible populations.

To support the authorization for emergency use of a single Moderna booster dose, the FDA analyzed data from a phase 2 trial, in which 149 adults who received the 2-dose 100-μg series, the dose authorized under EUA, plus the 50-μg booster dose were evaluated for immunogenicity. Results showed that the antibody response of the 149 participants against SARS-CoV-2 virus 29 days following

a booster dose demonstrated a booster response, according to the FDA press release.

To support the single booster dose of the J&J vaccine, the FDA analyzed immune response data in 39 participants from a study that included 24 participants aged between 18 and 55 years and 15 participants aged ≥ 65 years. Participants received a booster dose approximately 2 months after their first dose, and the results demonstrated a booster response, the agency noted in the press release.

For the mix and match EUA, the FDA cited data from a clinical trial conducted by the National Institute of Allergy and Infectious Diseases that showed heterologous boosters produced an immune response, with no new safety concerns.

“We will work to accrue additional data as quickly as possible to further assess the benefits and risks of the use of booster doses in additional populations and plan to update the healthcare community and public with our determination in the coming weeks,” added Marks.

The FDA also urged clinicians to follow the recommendations that will be provided by the Centers for Disease Control and Prevention after a meeting of their Advisory Committee on Immunization Practices on Thursday, which are subject to approval by the CDC director.