Sunday, the first of the Pfizer vaccines rolled out of the plant in Kalamazoo, MI on their way to all 50 states to begin the process of vaccinating Americans against COVID-19. Monday, those doses will end up in the arms of healthcare workers across the nation to help protect them as they serve the public. While we’ve been waiting for this day for months now, there is some level of skepticism and worry that we may have gotten here a little too fast. After all, haven’t we heard that it takes years to develop a vaccine? In this case, the timeline for the vaccines actually did start years ago. So, let’s dig into how this happened and what protections the vaccines provide.
For starters, I should remind everyone that I’ve had a stake in this game since last August when I was selected as a volunteer for the Moderna trial. You can read all about my research on mRNA vaccines and my own experience to learn more why I have this interest. To keep you updated, I’m still doing fine and looking forward to this Thursday when CDC’s ACIP meets to review and possibly recommend Moderna’s vaccine for EUA. After that will come the FDA approval and finally another meeting of the ACIP to recommend usage by the CDC to address the pandemic.
The Vaccine Timeline
But how did we get here so fast and were any corners cut? There is a great article at New York Magazine titled, “We Had the Vaccine the Whole Time” which lays out a lot of the details behind how we got to a vaccine so fast. I’ll sum up a few of the points in the article, but I highly recommend you reading it. In most cases, we are dealing with a disease that is so novel research must be done to understand more about how it infects our body and what is the key component to target to stop its spread. In this case, that happened when we first saw SARS in 2003. The SARS virus was essentially a cousin of this virus in that it had a spike protein that allowed the virus to attach to a cell, import into the cell, and replicate.
While SARS was almost as contagious as SARS-CoV-2, it was contained by some pretty draconian measures that eventually led to its eradication. Why were we not able to contain SARS-CoV-2 in much the same way? There will probably be many volumes written about the path of the latest coronavirus, but that’s for the future. Now, SARS-CoV-2 has claimed over 300,000 people in the US and until the nation reaches herd immunity, will continue to kill those vulnerable to the disease.
What we did learn from that earlier pandemic was how the virus was constructed and how it could be dealt with using a vaccine. Because it was eliminated, there was no need for a vaccine. But that didn’t mean one wasn’t in the works. In an article in Nature Reviews Microbiology, the details of the virus are described which match up almost identically to SARS-CoV-2 right down to the way the spike protein binds to the ACE2 receptor.
From the article, “The S protein plays key parts in the induction of neutralizing-antibody and T-cell responses, as well as protective immunity, during infection with SARS-CoV. In this Review, we highlight recent advances in the development of vaccines and therapeutics based on the S protein.”
Furthermore from the article, “The roles of S protein in receptor binding and membrane fusion indicate that vaccines based on the S protein could induce antibodies to block virus binding and fusion or neutralize virus infection. Among all structural proteins of SARS-CoV, S protein is the main antigenic component that is responsible for inducing host immune responses, neutralizing antibodies and/or protective immunity against virus infection. S protein has therefore been selected as an important target for vaccine and antiviral development.”
Making a Vaccine
Based on this knowledge, we knew what needed to be attacked. We just needed a vaccine to attack it. Once the genetic code was published by the Chinese in early January, vaccine makers around the world started their work in building various vaccines using different vectors, all targeting the spike protein. The two that made it to EUA first were based on mRNA. In fact, Moderna had their vaccine developed before China even acknowledged human-to-human transmission.
Trials for Moderna started in March based on a new approach for delivering the synthetic mRNA strand into the body successfully. Pfizer’s trials started in May using a slightly different delivery approach. Those differences are part of the reasons Pfizer’s vaccine must be kept so much colder than Moderna’s. Along with those trials, investments were made through Operation Warp Speed to prepare and build manufacturing for the Moderna vaccines along with Moderna’s partnership with Lonza.
Contracts were signed with most major developed countries to purchase the vaccines if they became approved for EUA with millions of doses to be delivered shortly after approval. That alone is something we never saw with other vaccines. But these all hinged on successful trials.
With Pfizer’s approval of EUA with 95% efficacy and Moderna’s pending approval with 94% efficacy, both companies are expected to deliver doses for up to 35 million people in the first phase. In the next quarter, both will deliver doses for another 100 million people.
As a Moderna trial volunteer, I can honestly attest that Moderna’s vaccine is safe. That doesn’t mean you’re going to get the shot and not feel a thing. You will feel some side effects, but they last only a day. To protect yourself and others, that’s a small price to pay for such substantial benefits.