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.
The following describes the role and scope of advisory panels to the U.S. Food and Drug Administration and Centers for Disease Control and Prevention.
WHAT IS THE ROLE OF ADVISORY COMMITTEES TO U.S. HEALTH AGENCIES?
The U.S. FDA and CDC each convene advisory committees comprised of independent experts to provide advice and recommendations on a broad range of public health issues, including drug approvals.
The FDA's Vaccines and Related Biological Products Advisory Committee (VRBPAC) and the CDC's Advisory Committee on Immunization Practices (ACIP) are two of these panels.
In some instances, FDA will ask its VRBPAC members to vote on whether a vaccine should be approved, and for which population. If the agency does approve the vaccine in question, the CDC will ask its ACIP committee to vote on how it should best be administered to Americans. In both committees, a simple majority vote will become the panel's recommendation.
In the case of Pfizer (NYSE:PFE)'s COVID-19 booster, VRBPAC endorsed a narrower guideline than originally requested by the drugmaker. The CDC's advisers narrowed their recommendation further.
WHO SERVES ON THE ADVISORY COMMITTEES?
ACIP's 15 members are mostly doctors who have expertise in how to best administer vaccines, including the timing and target populations. Candidates are nominated or can nominate themselves. Members are reimbursed for travel expenses and can receive an optional honorarium of $250 for each day the committee meets.
The membership of FDA's VRBPAC also mostly consists of doctors, many of whom specialize in infectious diseases. Candidates with minimal conflicts of interest can apply or be nominated to the FDA. Members of FDA advisory committees receive travel and per diem costs if they are accrued.
CAN THE AGENCIES DISREGARD ADVISORY COMMITTEE ADVICE?
Yes. While both agencies generally end up in agreement with the recommendations reached by their outside advisers they are not binding. The ultimate responsibility for making the final decisions rests with the heads of the respective agencies.
"This was a scientific close call. In that situation, it was my call to make," CDC Director Rochelle Walensky said of her decision for a broader booster rollout after weighing the advisory panel's recommendations.
Some scientists said Walensky was justified in insisting on additional protection for frontline workers, such as nurses and doctors caring for COVID-19 patients. Others questioned whether the broad definition of high-risk jobs opened the door to a wider use of boosters than necessary, particularly in young men who may be at higher risk of rare heart inflammation following the shots.