The US FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) voted unanimously to recommend the Emergency Use Authorization (EUA) for a booster dose of the Pfizer/BioNTech COVID-19 vaccine (brand name “Comirnaty”) in individuals 65 years of age and older and individuals at high risk of severe COVID-19.

The committee recommended that the additional dose be administered at least six months after the two-dose series. The panel also agreed that healthcare workers and others at high risk for occupational exposure should be included in this EUA, according to the companies.

VRBPAC is made up of independent experts who advise the FDA on scientific and regulatory matters, including the evaluation of vaccine safety and efficacy.

At this time, VRBPAC did not vote in favor of approval of a booster dose for the full population for which Pfizer and BioNTech submitted their supplemental Biologics License Application, which was individuals 16 and older. The same data have recently been submitted to the European Medicines Agency (EMA) and will be filed with other regulatory authorities in the coming weeks. The companies remain vigilant and continue to generate relevant COMIRNATY booster dose data for evaluation for future licensure in further groups as well as to address emerging variants of concern.

The FDA is expected to make its decision in the coming days. This decision could allow COMIRNATY to be the first COVID-19 vaccine with a booster authorized in the U.S.

“Today the VRBPAC reviewed data from our clinical program showing a favorable safety profile and strong immune responses against SARS-CoV-2 after a booster dose of our vaccine. These data, and the larger body of scientific evidence presented at the meeting, underscore our belief that boosters can be a critical tool in the ongoing effort to control the spread of this virus,” said Kathrin U. Jansen, Ph.D., Senior Vice President and Head of Vaccine Research & Development, Pfizer. “We thank the committee for their thoughtful review of the data and will work with the FDA following today’s meeting to address the committee’s questions, as we continue to believe in the benefits of a booster dose for a broader population.”

“We are committed to support the ongoing efforts to reduce infections and COVID-19 cases. The data we submitted to the FDA, EMA and other regulatory authorities underline that a booster induces a strong immune response against all tested variants of concern and may contribute to address a public health need,” said Özlem Türeci, M.D., Co-founder and Chief Medical Officer of BioNTech.

VRBPAC based its recommendation on the totality of scientific evidence shared by the companies, including data from their clinical program evaluating the safety, tolerability and immunogenicity of a booster dose of COMIRNATY. A booster dose of the vaccine elicited significantly higher neutralizing antibody titers against the initial SARS-CoV-2 virus (wild type), as well as the Beta and Delta variants, when compared with the levels observed after the two-dose primary series. The reactogenicity profile within seven days after the booster dose was typically mild to moderate, and the frequency of reactions was similar to or lower than after dose two. The adverse event profile was generally consistent with other clinical safety data for COMIRNATY.

Real-world surveillance data also were presented to the VRBPAC by the Israel Ministry of Health, providing further support for the public health impact of boosters. The data presented from Israel included an analysis published this week in The New England Journal of Medicine. The analysis comprised approximately 1.1 million individuals ages 60 years and older who were eligible for a booster dose of the vaccine between July 30 through August 31, 2021. No new safety signals were observed, and reported adverse events were lower than those observed after dose two. The analysis showed that a booster dose restored very high levels of protection against COVID-19 infections and severe disease in this period when Delta was the dominant strain. Individuals who received the booster dose were less likely by a factor of 11.3 (95% CI: 10.4, 12.3) to develop a confirmed infection and less likely by a factor of 19.5 (95% CI: 12.9, 29.5) to develop severe illness compared to those who were previously fully vaccinated but did not receive a booster dose. The additional protection after receiving a booster translated to vaccine effectiveness comparable to levels seen early in the country’s vaccine rollout (an estimated 95%), when the Alpha variant was predominant.

Under the EUA of the Pfizer-BioNTech vaccine in the U.S., a third dose was previously authorized for individuals at least 12 years of age who have undergone solid organ transplant, or who are diagnosed with conditions that are considered to have an equivalent level of immunocompromise. This authorization of a third dose for immunocompromised individuals is separate and distinct from the booster dose reviewed by VRBPAC today. The third dose for immunocompromised individuals is meant to address the fact that these individuals sometimes do not build enough protection after two doses of the vaccine. In contrast, the booster dose recommended today by VRBPAC for EUA refers to an additional dose of the vaccine that is given to those who have built enough protection after the primary two-dose vaccination series, but may have decreased protection over time due to waning of immunity.