The FDA’s Vaccines and Related Biological Products Advisory Committee (VRBAC) will review the available data for Pfizer/BioNTech’s SARS-CoV-2 vaccine on Thursday and Moderna’s on Dec. 17.
If the panel votes to authorize the vaccine under consideration, HHS Secretary Alex Azar has said that the FDA could grant an emergency use authorization (EUA) within 24 hours. An emergency meeting of the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control and Prevention (CDC) would be called as well. While ACIP last week made its recommendation on which groups should receive the vaccine first, the committee also recommends specific vaccines to be used once they have been authorized or approved by the FDA.
If the FDA grants an EUA for the Pfizer/BioNTech candidate this week, a vaccine against the SARS-CoV-2 virus, which causes COVID-19, could be available for distribution in the US by Dec. 12 with two available by Dec. 20. Pfizer and Moderna have said that they each expect to produce 20 million doses for the US by year-end, for 40 million in total.
The possible authorizations for the vaccines mark a milestone in a historic global effort to protect people against a virus that has, in a year, killed and sickened tens of millions and caused economic calamity on a vast scale. In the US, as of Dec. 2, more than 270,000 people had died of COVID-19, according to a tracker maintained by Johns Hopkins University. Globally, the number of dead was approaching 1.5 million. With naturally obtained herd immunity likely far in the future almost everywhere, safe and effective vaccines likely will prove to be the path toward an end to the crisis.
On Dec. 2, the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) granted a temporary authorization for emergency use of Pfizer and BioNTech’s COVID-19 vaccine (Pfizer’s press release is here).
The UK announcement came a day after ACIP in the US voted to prioritize healthcare workers and long-term care facility residents for immunization once the FDA authorizes a vaccine. The MHRA began a rolling review of the Pfizer/BioNTech vaccine in October. Its decision is based on data from the companies’ Phase III clinical study. That trial found an efficacy rate of 95% for the vaccine (see HRI’s breakdown of the trial results). MHRA also examined data from preclinical, Phase I and Phase II studies as well as manufacturing and quality control analyses (see MHRA’s statement here).
The Pfizer/BioNTech vaccination consists of a prime and a booster shot given 21 days apart. Both the Pfizer/BioNTech and Moderna vaccines use messenger RNA (mRNA) to encode harmless segments of a key part of the SARS-CoV-2 virus. Upon injection, the mRNA is delivered to cells that then use the mRNA as a blueprint to make the virus’ protein segments.
Once the body senses these virus proteins, it mounts an immune response against them. This process prepares the body’s immune system should it encounter the SARS-CoV-2 virus. The technology is still relatively new; beyond the new MHRA authorization, there are no approved mRNA vaccines or therapies for use in humans in the US or elsewhere.
As the UK prepares to distribute the Pfizer/BioNTech vaccine, Americans now know who will be in the first wave of those vaccinated. ACIP voted 13-1 on Dec. 1 that two groups should be given priority: healthcare workers and residents of long-term care facilities.
The CDC said it expects vaccines to be released for distribution in increments of 5 million to 10 million per week once one or more is authorized. Because of this complexity, there may need to be sub-prioritization in the early weeks of vaccine availability. At the meeting, the CDC outlined how health systems and care facilities could sub-prioritize within these populations. For example, the center suggested that healthcare workers with direct patient contact or those handling patient specimens be among the first within a facility to be vaccinated, while residents at skilled nursing facilities be first, followed by those individuals at assisted living centers.
Additionally, members of the ACIP recommended that primary care offices be among the very early sub-prioritization categories, as these healthcare workers are often the first to see COVID-19 patients when they are at their most infectious, just as symptoms are starting or when they are still potentially asymptomatic.
While the full safety and side effect profiles of the COVID-19 vaccines are unclear, companies such as Pfizer/BioNTech and Moderna have reported some side effects, such as fatigue and muscle soreness, that could cause disruptions in an individual’s daily activities. As a result, the CDC also suggested that health systems not vaccinate everyone in the same unit on the same day, staggering the vaccinations and minimizing the potential of too many healthcare workers sidelined at the same time due to side effects.
In the UK: Under an earlier agreement, Pfizer/BioNTech will supply the UK with 40 million doses of the vaccine dubbed BTN162b2. The companies said they would deliver the doses throughout 2020 and 2021 “to ensure an equitable allocation of vaccines across the geographies with executed contracts.” Pfizer said the first doses are expected to arrive in the UK “in the coming days.”
The vaccines must be shipped and stored at ultra-low temperatures (minus 70 degrees Celsius), and the company has designed special shipping packages equipped with GPS and temperature monitors that can store the vaccines for up to 30 days. The company will ship vaccines from its large freezer storage facilities in Belgium and Michigan with extra capacity in Wisconsin and Germany, according to the UK’s The Guardian newspaper.
In the US: The CDC said at the Dec. 1 ACIP meeting that through its discussions with states, most estimate that they could have healthcare workers vaccinated with the first dose in three weeks. To expedite the process once a vaccine is approved in the US, the CDC asked states and healthcare facilities to submit their allocation requests (e.g., the number of people they expect to vaccinate) to the agency by Dec. 4.
There are about 21 million healthcare workers in the US and 3 million long-term care facility residents, according to the CDC. The second dose of the Pfizer vaccine is administered 21 days after the first; Moderna’s is given 28 days later. Under an optimal delivery scenario, and assuming that additional doses beyond the 40 million become available in January, if nearly all healthcare workers receive the first shot within three weeks of authorization (by Jan. 2), they could complete the vaccination course by the week of Jan. 25.
Most skilled nursing facilities are expected to participate in the national pharmacy partnership for long-term care facilities, in which a total of 15,353 facilities (99%) have enrolled. Through this partnership, retail pharmacy workers will come to the facility three times to vaccinate the staff and residents.