For many, Covid vaccines are a beacon of hope. But the revolutionary power of one particular group of therapies may go far beyond fighting the current pandemic.
By successfully using the body’s own cells as protein factories to combat the virus, mRNA-based treatments have given a clear demonstration of how the technology could both speed up the development of vaccines in future and be used to treat other diseases - even cancer.
Scientists first discovered how DNA regulates life in our cells six decades ago, identifying the special messenger RNA (mRNA) molecules that translate genetic information into instructions for producing the proteins that run the body’s complex biological processes.
Since then, biologists have been trying to find ways to hijack that process. The aim has been to develop an alternative to traditional vaccine development methods, which involve introducing a weakened or dead virus into the body to trigger an immune response.
Efforts have focused on inserting lab-grown messages into the body, including recipes for the viral proteins that immune cells need to develop an immune response to an illness.
Success has been hard to come by. One problem was that the mRNA was inherently unstable. Another was that the reaction it provoked in the body was hard to control. More often than not, the immune response was either too weak or much too strong.
That all changed when Covid-19 rapidly morphed into the deadly global pandemic we know today.
It proved to be the incentive mRNA proponents needed to redoubled their research efforts – and the work finally paid off with the approval of the first mRNA vaccines in late 2020.
“I don’t think that there is any doubt that mRNA-based vaccines will change the landscape,” says Bogi Eliasen, head of health at the Copenhagen Institute for Future Studies.
It is still early days, but it looks like mRNA vaccines can be developed more quickly than traditional ones.
Moderna, the biotech company behind one of the two main mRNA anti-Covid therapies, reports that its mRNA vaccine went from gene sequencing to the first human injection in just 63 days. Pfizer/BioNTech, makers of another mRNA Covid vaccine, told of a similar trajectory.
Of course, there were many other factors at play as the world came together against a powerful common threat – including record-beating funding, previously unseen levels of cooperation between countries, universities and companies and, not least, a degree of luck. And not all of the Covid vaccines use the mRNA technology.
Plug and play
The advantages go beyond speed. mRNA treatments also give virologists the ability to adjust the formula relatively easily in response to virus mutations – something coronavirus has shown a strong propensity for.
“The mRNA technology is made on a platform which is pretty much ‘plug and play’, so in case the virus mutates, it is fairly easy and fast to change the vaccine. Therefore, mRNA-based vaccines offer a comparatively simple and rapid solution to unpredictable changing or evolving pathogens,” says Eliasen.
Another plus is that mRNA vaccines can be produced at smaller facilities and on a smaller scale than traditional vaccines, making them cheaper and adding to their nimble credentials.
On the flip side, mRNA vaccines so far have been highly reactogenic – meaning they generate a strong immune response, potentially bringing unpleasant side effects such as sore arms, headaches and fever.
Nonetheless, mRNA’s success in the fight against Covid should bolster its use against other diseases – something that biotech companies are already been working on.
“The scientific community had been researching mRNA vaccines for several viruses for years and I expect the success of the Covid-19 vaccine will further this development,” says Eliasen. Its nimbleness, in particular, could be useful against influenza, “which is difficult to target due to the fast mutation rate and the many strains that exist,” he adds.
Biotech companies are also researching the use of mRNA against zika, rabies and cytomegalovirus, among others. And, in time, it could play its part in securing the holy grail of the vaccine world – an effective tool against cancer. BioNTech and Roche are testing an mRNA cancer vaccine against melanoma, while Moderna is carrying out trials in ovarian cancer– though both are in early stages of development.
“Currently there are several ongoing clinical trials using mRNA vaccines against different types of cancer including prostate, melanoma and lung cancer. Because of the versatility of mRNA vaccines, they can even be tailored specifically to each patient’s tumor, thereby taking personalised medicine to the next level,” says Eliasen.
“The basic understanding of the biology of the viruses and the immune response they trigger must be in place, but when it is I definitely see a future where it is possible to vaccinate diseases such as zika virus, malaria and hopefully even HIV.”
