Both Pfizer/BioNTech and Moderna have released preliminary stage III results of their COVID vaccine trials, and both look really good (over 90% efficacy). They both also represent a totally new kind of vaccine. Vaccines work by giving your body a “sheep in wolve’s clothing” — something that your body sees as a virus, which it then learns how to attack, but which isn’t actually dangerous. The first vaccines were small doses of related diseases that weren’t as dangerous (e.g., the very first vaccine, against smallpox, was injecting people with cow pox, a related disease that only has mild symptoms instead of being deadly). Today, we attempt to construct new vaccines by growing proteins from yeasts and other biotech techniques to generate these sheep.
Both the Pfizer/BioNTech and Moderna vaccines are based on messenger RNA. In case you’re having trouble recalling your freshman biology course, mRNA are little strands of genetic material that tell cells which proteins to produce. This is “genetic engineering”, but not in the sense that it’s changing your DNA. Rather, these little messengers show up, and tell your cells to build something new (in this case, a protein that resembles the spiky shell on the outside of corona virus). Your cells make that protein, and then go back to their day job. The messages themselves, the mRNA strands, are destroyed naturally by the cellular process, which means you can completely control how much of the new protein is made, and the “half life” of the mRNA just by injecting different amounts. Once the new proteins are manufactured by your body, the immune response sees them as an enemy, and learns to fight them. Voilà! Immunity. If successful, these will be the first mRNA based vaccines to reach market (about a dozen have previously made it to human trial, but none were ultimately approved). Making mRNA has gotten much, much cheaper over the last decade, and will continue to do so. This means that scientists can create hundreds or thousands of mRNA messages to attempt to build a new protein, which means better results can be achieved much more quickly. Better, because the end protein being built is closer to the real attack vector, and therefor the body learns to fight it better; faster, because it’s designed rather than guessed. How much faster? Well, if this works, not only will it be the first vaccine ever developed in under a year, it would be the first one ever developed in less than five years. Perhaps more importantly, this technique need not be confined to infectious diseases. Similar methods could be used to fight cancers, or achieve any number of other medical breakthroughs. There are still a lot of challenges in fighting covid, even if these are approved — and these aren’t yet approved — but if they make it through, it could be a seismic shift in biotech.