By Michael Erman

(Reuters) – The U.S. CDC on Friday backed a booster shot of the Pfizer/BioNTech COVID-19 vaccine for Americans aged 65 and older, adults with underlying medical conditions and those in high-risk working and institutional settings despite calls for a narrower scope by a panel of expert advisers that would exclude the latter group.

This article describes the role and scope advisory panels for U.S. Food and Drug Administration and Centers for Disease Control and Prevention.

HOW ARE ADVISORY COMITTEES INTERESTED IN U.S. HEALTH AGENCES?

Each U.S. FDA or CDC has advisory committees made up of experts who provide guidance and recommendations regarding a wide range of health topics, including drug approvals.

Two of these advisory committees are the FDA’s Vaccines and Related Biological Products Advisory Committees (VRBPAC), and the CDC’s Advisory Committee on Immunization Practicess (ACIP).

FDA might ask VRBPAC to cast their vote as to whether or not a vaccine should go ahead. The CDC will request its ACIP committee vote to determine how the vaccine should be administered to Americans if the agency approves the vaccine. Both committees will vote by simple majority to determine the panel’s recommendations.

In the case of Pfizer (NYSE:)’s COVID-19 booster, VRBPAC endorsed a narrower guideline than originally requested by the drugmaker. The CDC advised further narrowed the scope of their recommendation.

WHO SERVES ON ADVISORY COMITTEES

ACIP’s fifteen members include doctors, who are experts in the best ways to administer vaccines. This includes timing and targeting populations. Candidate can either be nominated by others or themselves. For each meeting, committee members can be reimbursed travel expenses. They also receive $250 honorarium.

FDA’s VRBPAC is mainly composed of doctors who specialize in infectious disease. No conflicts of interest are required to apply for or nominate candidates to the FDA. If they have been accrued, members of FDA advisory boards receive per diem and travel costs.

DO AGENCIES REFUSE TO REGARD ADVICE OF THE ADVISORY COMITTEE?

Yes. Yes. Although both agencies tend to agree with outside advisors’ recommendations, they are not binding. Final decisions are made by the head of each agency.

This was a close scientific call. After considering the recommendations of the advisory panel, Rochelle Walensky, CDC Director said that it was her call to expand the booster program.

Some scientists believe Walensky had a right to demand additional protections for frontline workers like nurses or doctors who treat COVID-19 victims. Other scientists questioned whether the expansive definition of high-risk job openings allowed for more booster use than was necessary, especially among young men with a higher chance of developing rare heart disease.