The first COVID vaccines have been approved and are being rolled out across the US. To date several hundred thousand have received their first dose of the Pfizer-BioNTech vaccine, which was the first to get the FDA Emergency Use Authorization (EUA). Many Americans are feeling anxious and have questions. Here’s a snapshot of the vaccine facts right now.
Approved and Expected Vaccines
The new coronavirus strain, SARS-COV2, emerged at the beginning of 2020 and causes the illness now known as COVID-19. Amazingly, by June over 150 different COVID vaccines were in development. Billions of dollars were put forward by the governments of the world for the endeavor.
Now we are starting to see the results of these historic efforts, with two COVID vaccines receiving EUAs from the FDA this month and another expected in January. These are the fastest vaccine development efforts and approvals of all time.
The first three vaccines were all developed with a brand new nucleic acid technology based on RNA. The RNA vaccines work by giving the body the genetic codes needed to produce the antigen that provokes an immune response. The vaccines include fat globules that contain genetically engineered COVID RNA strands that are instructions for building the COVID spike protein. The RNA goes into our cells and uses the cellular machinery to start making COVID proteins, the cells break open and release the proteins, and then our immune system reacts to them. In this way, the body becomes a sort of vaccine manufacturing unit. The three RNA vaccines which are available now or expected very soon are:
- Pfizer-BioNTech BNT162b2 - has EUA and available now
- Moderna mRNA-1273 - has EUA and available soon
- Oxford-AstraZeneca Covishield - EUA expected in early January
The current leader among the ranks of the non-RNA vaccines is Novavax’s NVX-CoV2373. It’s made using recombinant nanoparticle technology to introduce a protein subunit that prompts an immune response. Its late-stage study results are expected in early 2021. Analysts have high expectations for the vaccine since early testing results showed high antibody responses and virtually no side effects. It may not be available until late 2021.
Are COVID vaccines safe and effective?
Both of the approved vaccines seem to be quite safe and highly effective, with clinical trials finding the Pfizer-BioNTech vaccine 95% effective, and Moderna's 94.1% effective, at preventing symptomatic disease.
How many doses are required?
All of these early vaccines are being designed as a two shot series. For example, the Pfizer-BioNTech vaccine is given in 2 doses 3 weeks apart.
Is the Emergency Use Authorization (EUA) the same as FDA approval?
Not exactly. The EUA is an expedited approval process used to make unapproved drugs available in a state of emergency without going through the normal, lengthy approval process. The FDA granted the Pfizer-BioNTech EUA stating that it “has conducted a thorough evaluation of the available safety, effectiveness, and manufacturing quality information,” and the vaccine “may be effective in preventing COVID-19” and the “known and potential benefits outweigh the known and potential risks.”
Do the vaccines stop transmission?
At this time the manufacturers and the FDA are not sure whether the vaccines will stop the transmission of the virus.
How long does vaccine immunity last?
The manufacturers and the FDA do not know how long the vaccine-acquired immunity will last. They also do not know how long natural immunity to COVID-19 lasts.
Benefits of COVID vaccines?
The vaccinated had strong immune responses with robust production of antibodies against the COVID-19 infection. Manufacturers and regulators are hopeful that will mean it prevents people from developing and transmitting the illness. For now they are only confident about the vaccine’s ability to lessen severe illness and symptoms. The rest remains to be proven.
What happens if the virus mutates?
Mutations in the virus are possible and there already seem to be mutated strains circulating, especially in Europe. Vaccine experts are optimistic that the vaccines will still work because of the way they were designed, but time will tell.
Side effects of COVID vaccines?
Most will have minor side effects such as pain at the injection site. Participants in Moderna's trial reported more reactions than in the Pfizer trials including injection site pain, fatigue, headache, fever, and muscle pain. Many people had more side effects after the second dose. A few rare cases of anaphylaxis and Bell’s palsy have been reported.
Who will get the vaccines first?
The CDC has defined the priorities for the administration of the vaccines.
- Phase one will vaccinate health care workers and long-term care residents.
- Phase 2 includes adults 75 and older and front line essential workers.
- Phase 3 rolls out to adults between 65 and 75, those between 16 and 64 with high-risk medical conditions, and “other essential workers.”
- Phase 4 will be for the rest of the population over 16 years old. Experts estimate this group will begin receiving the vaccine by mid-summer 2021.
Are there any risks to taking the vaccines?
The studies have shown the vaccines to be safe. However, since they are new there may be some risks that have not been identified. Some concerns include:
- After the development of vaccine immunity, non-neutralizing antibodies can lead to an exaggerated immune response with a challenge from the wild virus.This is known as antibody-dependent amplification (ADE) and has been seen in some prior attempts at creating coronavirus vaccines. So far this has not been seen with any of the current vaccine candidates.
- Anaphylaxis reactions are a possibility and have been seen in several early vaccine recipients. Polyethylene glycol is one vaccine ingredient that was identified as possibly causing these reactions. Medical authorities are recommending caution for those with prior severe allergic reactions to vaccines or vaccine ingredients.
- Long-term adverse effects cannot be known at this time. The duration of studies are only several months long so we are unable to assess any late-emerging effects. Some safety skeptics warn that autoimmune conditions could develop up to two years after vaccination.
The FDA’s assessment for the EUAs was that the benefits of the vaccines outweigh any known or potential risks.
Were the vaccines tested enough?
The development of these vaccines was shortened significantly and that includes the testing phases. Pre-clinical trials were done concurrently with safety/dosing trials and all trials were shortened dramatically. The three normal phases of testing--dosing, safety, and efficacy-- were combined into two: safety/dosing and safety/efficacy. Safety testing was not done as a separate trial like it usually would be. The health authorities feel confident that the trials as performed were adequate to evaluate the vaccines.
Are the manufacturers liable if anyone is injured by the vaccines?
All of the vaccine makers are indemnified from liability by most countries, including the US and the EU.
The rollout of these vaccines and others that are expected next year should mean the beginning of the end of the COVID-19 pandemic. Even if the vaccines are not able to fully stop transmission, they will be able to protect the vulnerable so that we can get back to more normal social interactions. Hopefully by this time in 2021 we will be celebrating our great victory over COVID-19 with big parties and lots of hugs!