A week ago, pharmaceutical giants Pfizer Inc. and BioNTech SE announced to the world that they had managed to develop an experimental Covid-19 vaccine, which could be 90 per cent effective at preventing the virus. Pfizer’s CEO Albert Bourla hailed it as “a great day for science and humanity” and regarded this discovery as the greatest medical advancement in the last century. The company added that while it will be sharing additional safety data generated from participants in the coming month, the vaccine will not be ready for distribution to the general public any time soon.

In accordance with guidelines enforced by the US Food and Drug Administration, both companies will not put forward an emergency use authorisation until patients in their study have been free of any complications for a minimum of two months after their second dose. And they are hoping to complete all observations by end-November. Although this piece of good news may bring an end to the pandemic, it is premature to start celebrating as data from the trials have not been finalised yet. For now, here’s what we know about Pfizer’s Covid-19 vaccine.

1. The vaccine was discovered by two German-Turkish scientists.

Billionaire scientists Ugur Sahin and Ozlem Tureci first set up BioNTech in the central German city of Mainz in 2008 and have spent their entire life researching infectious diseases and treatments for cancer. During this pandemic, they dedicated their research to genetic modification, and their efforts were rewarded when their partner Pfizer reported that the vaccine they had created was 90 per cent successful. The couple, who are both trained physicians, have a reputation for being charitable and this discovery has catapulted them to celebrity status.

2. The vaccines will be distributed first to those most in need.

Before Pfizer and BioNTech can start distributing vaccines, regulators need to give the thumbs-up first. Thereafter, the government will give the vaccine to those whom they deem as a priority. The first in line will likely be healthcare personnel, people living in nursing homes or elderly care facilities and those who are older and weaker with underlying health issues.

3. The vaccine will be limited in supply.

Once the initial supplies of the vaccine are authorised, they will be available in limited quantities. Pfizer said that approximately 50 million doses could be available globally by the end of the year, and in 2021, this amount will increase to 1.3 billion.

4. The vaccine has complex and stringent storage requirements.

One issue regarding this vaccine is its complicated logistics. The vaccine requires storage in an extremely cold environment of (at least) minus 70 degrees Celsius and below, which is considerably colder than most vaccines. This is because the vaccine uses synthetic mRNA to activate the immune system against the virus and without such freezing temperatures, the integrity of the mRNA and lipid nanoparticles will be compromised. This could be problematic for tropical countries and rural areas that may lack the proper facilities and resources to store the vaccine. Even developed countries like Japan have said that their hospitals do not have the proper equipment to effectively keep the vaccine. In fact, according to Soumi Saha, the senior director of Premier, Inc. such freezers are “almost like unicorns in healthcare” because “they’re far and hard to find.” He also added that no one seems to have enough experience working with a vaccine at such a temperature.

5. The vaccine has its own kind of packaging called “pizza boxes.”

Despite the fact that the vaccine requires extremely low temperature storage conditions (causing concerns over transportation to arise), Pfizer’s scientists remain confident that the company’s special packaging called “pizza boxes” are able to keep the vaccine cold. The vaccines will not only be packed with (replenishable) dry ice in these containers, with highly insulated corners to keep the temperature constant for a few weeks, but also tracked while in transit to ensure that the person receives it in the right temperature. 

6. The vaccine is the first of its kind in the market.

Pfizer’s vaccine utilises mRNA technology to trick the body into producing protein that resembles the genetic material of the virus. The immune system learns to recognise and attack those protein bits, conditioning the body to react quickly to a real infection. Since no mRNA product has ever been approved by regulators, this will be the first of its kind, pending the green light from the US Food and Drug Administration. The good news is that this class of mRNA vaccines could make vaccines against other new pathogens a reality, if scientists are able to sequence its genetic material. One major impediment to the process of traditional vaccine development is working out how to emulate an external pathogen without repercussions. With mRNA vaccines, researchers can bypass that stage since cells are able to safely build defenses against a non-existent virus.

7. The vaccine comes with possible side effects.

Common reactions to the vaccine can include sore arms or fever, which are generally harmless. Both companies have repeatedly affirmed that apart from these minor after-effects, there are no other significant health concerns. They will continue to collect data and observe closely for any repercussions. mRNA has only been recently approved for use in humans, so it is possible that some people may be allergic to certain elements of the compound. Another point to note is the vaccine may not be as effective as compared to those used in clinical trials, since doctors tend to preselect their patients. In the real world, people who have underlying health conditions may not be accounted for.

8. The vaccine is not yet known to prevent severe cases.

Currently, there are studies in progress to determine how long the immunity will last as well as the possibility of any repeated exposure risks. Also, there is uncertainty as to whether the vaccine will be able to prevent severe cases that can be life-threatening, or if it can stop the “silent carriers”—people who carry the virus without symptoms.

9. The vaccine may not be able to prevent the transmission of Covid-19.

At this point, it has yet to be determined if the vaccine can protect us against the coronavirus, or if it simply contains the symptoms and stops them from developing after an infection. If it can completely prevent an infection, it should rightly be able to stop transmission from one person to another. However, if one does have an asymptomatic infection, he or she still has the potential of infecting others (albeit at a lower risk).