Race to a Cure Authors
- Dec 3, 2020

The Pfizer Vaccine: End of the Pandemic?

Just in these past couple of weeks, Pfizer released critical information about their new vaccine for the coronavirus. The results released on social media seem promising, but let’s debunk if it really is, and if we could see an end to the pandemic in the near future.

(Image courtesy of cottonbro via Pexels)

What is Pfizer?

If you aren’t super into pharmaceuticals, then Pfizer (pronounced FI-ZER) is definitely new to you. Pfizer is one of the main companies (if not the largest in the world) that produce drugs and is based in the United States. Together with other drug companies, the pharmaceutical companies are known as a ‘Big Pharma’.

The reputation behind ‘Big Pharma’ companies has been mixed. The obvious good that comes out of these companies, including Pfizer, is the development of medications that help with life-threatening illnesses such as the EpiPen, as well as everyday medications such as Advil. However, many lawsuits have been made against these companies for not disclosing the negative side effects of some of their drugs, along with carrying out unapproved clinical trials. Thus, it is important to keep in mind that the intentions behind these companies may be flawed and should be put into question.

Pfizer’s COVID-19 Vaccine

The vaccine that Pfizer has been working on for the past couple of months works in a unique way compared to other vaccines. In order to understand how different and interestingly Pfizer’s vaccine works, you should first know how typical vaccines work.

Let’s take the flu shot as an example (this is a reminder to visit your local pharmacy to get the flu shot for this flu season!). In order to gain immunity against the influenza virus, your body needs to be exposed to the flu particles, and this is done through the flu vaccine. The flu particles contained in the vaccine aren’t active and won’t make you sick. The flu particles are just dead pieces of the flu virus that your body detects as foreign objects, which then triggers an immune response by creating antibodies against the flu. This will help your body remember how to recognize and fight the flu in the future. The flu shot is an example of an inactivated vaccine.

Image of the influenza virus. (Cynthia Goldsmith)

What makes the Pfizer vaccine (called BNT162b2) different is that it doesn’t use traditional inactivated/dead virus particles to induce an immune response. Instead, the company has managed to take advantage of mRNA technology to introduce the virus’ RNA into the body and use the body’s cellular machinery to translate the corresponding protein/antigen. The protein encoded by the RNA is known as the ACE2 surface receptor. This is the same protein found on the coronavirus that the virus uses to target the body’s cells. By having the body express this protein, it will induce an immune response similar to how the flu vaccine does.

The ACE2 receptor used by coronavirus to enter the body’s cells. (National Institute of Health)

So why use mRNA-based vaccines? According to Pfizer, mRNA-based vaccines are more flexible and take less time to make compared to inactivated vaccines. The flexibility behind mRNA-based vaccines comes from the fact that viruses are constantly mutating. By expressing a protein that is found on all/most versions of the virus, you are able to gain immunity to more than one version of the virus. They also take less time to make because you only need to sequence and introduce a small piece of the virus’s genetic code, rather than have to grow the virus multiple times to inactivate and then introduce it.

Pfizer’s Early Results

Pfizer was one of the first companies to release early results from Phase 3 of their clinical trial involving over 43, 000 participants, in which half received the vaccine and half received a placebo. They reported it had a 95% efficacy rate (meaning it worked 95% of the time) and had no serious safety concerns besides fatigue and headaches. These results do look promising, but are they too good to be true? Especially with the reputation of Pfizer, it has caused some speculation.

Is this the end of the pandemic?

Not necessarily. You won’t be able to attend those awkward family dinners any time soon, but the future remains bright. It is expected that by the end of 2020, Pfizer will have made 50 million vaccines and about 1.3 billion by the end of 2021, so you could be visiting your doctor as soon as next year to get the coronavirus vaccine.