A few disclaimers: We are not medical professionals, please follow the CDC and governmental websites for updates and stay safe!
Exciting news! More Americans have received the COVID-19 vaccine than have tested positive for the virus and almost 30 million doses have been given out. Considering that there are currently not only one, but two COVID vaccines (Pfizer and Moderna) only less than a year before the first COVID case had been reported in Wuhan, China, this is incredible progress. One question that many of us may be asking is, how did this vaccine get developed so quickly?
How long does it take to make a vaccine?
In general, (COVID being the exception) vaccines take up to 10-15 years for scientists to produce, and it involves several complex stages:
1. Stage 1: Exploratory Research
The first step is conducting laboratory research. During this step, scientists will take 2-5 years to identify the antigens that are needed to help prevent the disease. Antigens are the active component that all vaccines have. You can think of antigens as a small part of the disease that the vaccine is trying to combat. The antigen is the part of the vaccine that stimulates the immune system to start producing antibodies (a protein that fights off antigens).
Stage 2: Pre-Clinical Stage
This is the stage where researchers conduct tests on cells, tissues, and animals to assess the vaccine’s immunogenicity. Immunogenicity is the ability of the vaccine to provoke the desired immune response. This is also the stage where researchers will use tests to evaluate the safety of the vaccine. This process usually takes about 2 years.
After this stage, the creators of the vaccine (most likely a private company) will submit an application for an Investigational New Drug (IND) to the Food and Drug Administration (FDA). Once approved by an Institutional Review Board (IRB), the researchers are allowed to begin clinical trials!
Stage 3: Clinical Testing on Humans
The clinical testing stage for vaccines is split into 3 parts:
The vaccine is given to less than 100 adult volunteers in a non-blind experiment. A non-blind experiment is where both the researchers and test subjects know whether they received the treatment or not. The goal of this stage is to assess the safety of the vaccine as well as to see if the desired immune system response happens.
A much larger group of volunteers receive the vaccine — some of the people involved in this phase may be those that are at risk of the disease. At this stage, scientists will perform what is called a blind experiment: there are two randomized groups, one will receive the actual treatment (the vaccine) and the other group will receive a placebo without their knowledge. The placebo is essentially a harmless pill that has no effect on the patient.
The longest and largest phase, taking up to 10 years and involving thousands of volunteers, the goal of this stage is to monitor side effects. Only about 1/3 of potential vaccines make it to this stage. Many other questions the researchers will consider are:
- Does the vaccine prevent disease?
- Does it prevent infection with the pathogen?
- Does it lead to production of antibodies or other types of immune responses related to the pathogen?
Stage 4: Approval and Licensure
After successful clinical trials, a Biologics License Application (BLA) is submitted to the FDA. The FDA while evaluate things like safety, potency (amount of drug required for the vaccine to be effective), and purity (quantity of antigen in the vaccine) and might conduct their own tests as well. The FDA approval process for the BLA will take up to 2 years. After approval, manufacturers can start to produce the vaccine in large quantities and be released for use! Throughout distribution, researchers will continue to monitor the vaccine for quality control.
Now that we know how long and tedious of a process it is to create a successful vaccine, how did the COVID vaccine get created so quickly?
1) Researchers worked together
During a global pandemic, scientists from around the world shared their research and therefore helped the process go quicker.
2) The research did not start from scratch
One common misconception is that research for the vaccine began when the first case of coronavirus was discovered in December 2019. However, research started years before. There are thousands of types of coronavirus, one of which is SARS-CoV-2. SARS stands for severe acute respiratory syndrome and was an illness that spread throughout North America, South Ameirca, and Europe during 2002-2003. SARS had already been researched heavily, and once the coronavirus outbreak began – scientists noticed the genetic similarity between SARS and COVID-19 and were able to use the research.
3) New mRNA technology
The COVID-19 vaccine is the first time that a mRNA vaccine has been distributed to the general public. Unlike traditional vaccines, mRNA vaccines do not require an antigen, instead they carry copies of the recipe for making the antigen. This makes them much quicker to develop. To learn more about how mRNA vaccines work, click here for an article by Standford Medicine.
4) Tons of funding
Because of the urgency of creating this vaccine, researchers received WAY more funding than normal. The US government invested in multiple companies to make the vaccine as fast as possible.
5) Emergency Use Authorization
The FDA granted Emergency Use Authorizations (EUA) to the two current COVID vaccines (Pfizer and Moderna). Under the EUA, FDA allows these vaccines to be distributed without going through much of the approval process that is traditionally required for any vaccine. Even though the COVID vaccine was granted a EUA, the vaccine is still monitored vigorously and still going through testing to ensure its safety and effectiveness.