As time goes on, and we are all still wearing masks and social distancing without any tangible end in sight, it seems more and more our only hope of restoring human interactions as we once knew it (and not having to wear a mask while having a hot flash) lay in the development of a vaccine for the COVID-19 virus instead of a cure. Vaccines are not a cure for a virus, as they provide a stimulus for the body to form antibodies to fight the virus if infected. That said, the race is on to produce the most effective vaccine in the fastest time frame possible. Having overseen immunization programs overseas, I know some of what is entailed in the manufacture, storage and distribution of vaccines, but everything I have written is readily available knowledge online.
Where We Are Now Producing a Vaccine
There are currently over 100 proto-vaccines in development around the globe.
By current estimates, we're likely to have a functional vaccine by the end of 2020. I will go on to describe what "functional" means later. The speed at which these vaccines are being produced is amazing, as normally vaccines require a decade or more to develop, hence the label "Operation Warp Speed" in the US. As amazing as this is, developing a vaccine so quickly, there are some caveats.
Research Phase
Normally, prior to human trials being conducted, which is vaccinating people with a proto-vaccine to see how they respond, there is usually 5 years of discovery and research, and testing on animals. The research phase for the coronavirus vaccine occurred in months, not years. So after months of research, we are now in human trials. Human trials occur in 3 phases.
Phase 1
Phase 1 is a safety trial of 50 or so people to make sure the vaccine doesn't cause obvious terrible side effects. The limitation with Phase 1 trials, is the small amount of people who receive the proto-vaccine, as sometimes, side effects don't become known for years afterwards. Such was the case with the rotavirus vaccine in the 1990's, which was to prevent the virus that causes vomiting and diarrhea in children. A serious side effect of this vaccine also caused intestinal intussusception or twisting of the bowels requiring surgery. I operated on one such child at TJUH. We don't want to see something like that happen again. Phase 1 usually lasts 1 to 2 years.
Phase 2
Phase 2 uses more people, around 1,000. Is still mostly checking to be sure the vaccine's components are not broken down in the body before they can stimulate antibody production. Phase 2 usually lasts 2 to 3 years. In the accelerated environment of the COVID-19 crisis, many drug manufacturers are running Phases 1 and 2 concurrently.
Phase 3
Phase 3 is the most clinically relevant phase where thousands of people are injected with the vaccine and then released into the general public, where the virus is still active. Ethics rules forbid infecting human test participants with a serious disease, so we cannot deliberately expose vaccinated people to the coronavirus. That means the only way to prove that a vaccine works is to inoculate people in a location where the virus is spreading naturally around them and see what happens to them.The goal for Phase 3 is for those injected with the vaccine to be confronted by the virus, in a population where the virus is active, so that we can find out which of the following occurs:
A) the inoculated don't get sick at all from the virus (are immune - best scenario)
B) they get sick but cannot spread the virus (kinda bad/kinda good)
C) they do not get sick but might still be able to spread the virus (kinda good/kinda bad)
D) they get sick but suffer less intense symptoms (such as what happens with chicken pox vaccine - not bad)
E) the vaccine does nothing at all (useless)
F) the vaccine actually makes people more susceptible to the virus (worst case scenario). Yes, this can happen.
Right now, eight of the over 100 vaccines that are under development globally are in Phase 3 trials. The Russians decided they didn't need Phase 3 and have gone ahead and approved their vaccine for general use as of August 13. Russia is not known for top notch medical science and has no virologists of note. So we can watch Russia to see what happens there. I wouldn't visit!
A Functional Vaccine
Now, what I meant by a "functional" vaccine:
When I say we'll have a functional vaccine in the fourth quarter of 2020, is that at least one of these 100 proto-vaccines (most likely one of the eight) will have made it through Phase 3 with a result of A, B, C or D. All those outcomes are considered good enough to qualify as "successful". But even if the vaccine comes with a solid "A" rating, that patients are immune to COVID-19, that hardly means the COVID-19 crisis is over, because then we will have to manufacture and distribute the vaccine.
Vaccine Manufacturing
Vaccine manufacturers use many different processes for creating and producing vaccines. Some vaccines require live virus which must be grown in large volumes (I would NOT want to work there). This would require significant biohazard lab expansions. Some vaccines just require snippets of RNA and can be produced in days. Same for some of the newer RNA techniques, using messenger RNA – like that for the vaccine being developed by Moderna, a Cambridge Massachusetts Bio-tech company, which are only now being used for human vaccines for the first time. Yes, for the FIRST TIME. Other manufacturing techniques use vats of yeast to produce vaccine (traditional method). This is a much more readily available substrate compared to some manufacturers that need an extract from a specific sort of Chilean soapbark tree that can only be harvested in the Southern Hemisphere's summer - this is not a joke. Bottom line, each vaccine uses a different process, the materials and processes are proprietary. They are all in the race, we will see which one wins.
Vaccine Distribution
Then there's distribution. The good news is that every country already has built-in, tried-and-true systems for the mass distribution and application of vaccines. The flu vaccine is the best example of this.
But there can still be distribution complications. Some vaccines require refrigeration. Some require freezing. Based on components and temperature requirements, each has their own peculiar demands for glass vials and syringes and even stoppers. Use the wrong packaging or transport method, and you've just wasted months of work and millions of doses.
Vaccine Efficacy and Longevity
Finally, there's the factor of vaccine efficacy and longevity of protection. Not all vaccines are created equal in this regard. Some might require a higher dose or even multiple doses to achieve protection. For example, the annual flu shot requires a higher concentration for the elderly in order to stimulate an immune response. The CanSino vaccine candidate, made by a Chinese biotech company, might not work in the elderly at all. If two doses are required – which is currently the best guess for the Jenna/Oxford UK vaccine candidate, which is in phase 3 in Brazil - then twice the production capacity will be needed.
If the vaccine triggers a strong immune response – like the BioNTech/Pfizer, vaccine candidate, headquartered in New York, appears to – that's great! But if protection only lasts a few months, we'll need to mass produce the vaccine for global use forever...or at least until we grind the virus out of the population. (Keep in mind humanity has only actually eliminated one virus – smallpox – to the point we could stop immunizations.)
While things will change week by week, at present, the UK Jenna/Oxford candidate seems to be on track to be deemed "successful" first, while the US Moderna candidate faces the fewest manufacturing challenges, and the US BioNTech/Pfizer candidate appears to be the most effective. There is not a lot of information about the Chinese CanSino vaccine candidate, but it will likely be significantly delayed, as the Chinese still need to perform Phase 3 trials, exposing inoculated patients to the wild virus in other countries, and few countries are likely to agree to this.
Best Case Scenario
The dream vaccine would be a one-shot vaccine delivered via nasal inhalant (no syringe required), be made from yeast, safe to store at room temperature, grant 100% immunity, and last a lifetime. Hopefully this is possible and if so, would be the biotech miracle of the ages if accomplished in a manner of months not years. Let's all pray for "best case scenario vaccine."
More Likely Scenario
It's more likely that the first "successful" vaccine to market will be one that requires two shots given two months apart, is fabricated using the pancreatic fluids of a llama (this is a joke), only lessens the impact of COVID-19 rather than outright preventing it, must be frozen for transport, and must be re-administered every six months. If a less than ideal vaccine such as this is the one that wins the race to be first to market, we'll keep developing alternatives until we find something better. Currently, the US has thrown $1 billion plus at each of the top three candidates, complete with pending orders for at least 100 million doses and these companies are already gearing up for production. So we have back up vaccine candidates.
When Will the Vaccine Be Available?
We'll likely identify one of the vaccines "successful" at some point in the fourth quarter of 2020, and with the time lags for manufacturing and distribution, and if the first vaccine is not American made, it will be another modern miracle if we can get the vaccine available to the public for widespread distribution by Spring of 2021.
In Closing
Vaccines are not cures for disease, but are meant to be preventative, as vaccines stimulate antibodies to form to be better able to fight the disease when infected with the virus. Currently one of our best treatments for those ill with COVID-19 is in fact antibodies, antibodies produced by people who have been infected with coronavirus and were well enough to donate their plasma upon recovery. The other way to combat a virus is to develop herd immunity. Once a person has been infected with and survives a virus, they are immune, and thereby are the safest people to be around. For most viruses, when 80% of the population is immune to a virus, the virus cannot survive in this population and goes away. If we absolutely could confirm there were no long term health consequences of infection with coronavirus in the young and given the relatively mild illness in the young, then promoting herd immunity through infection in the younger population would be a good option to remove the virus from human circulation. However, since we don't know the long term health consequences of infection with the coronavirus, I would not recommend going for herd immunity with COVID-19. So that leaves us with a vaccine as our best bet at defeating COVID-19 and getting back to "normal."
At the pace we are going, a vaccine for COVID-19 could be spring of 2021, with hospital workers and the vulnerable likely to be immunized first, followed by the general public. This is a stunning time frame, truly "Warp Speed."
