January 4-10 2021
How have vaccines been produced so quickly?
How has it been possible to develop a vaccine against COVID-19 in such a short period of time? This success is linked to the exceptional nature of the situation, of which 3 aspects might be underlined:
- Unlike other epidemics, many countries have simultaneously faced economic catastrophe, and the millions spent on alleviating the situation have meant that risks have been taken that would usually be impossible. In more normal times, it takes years to analyse the effectiveness and safety of a vaccine, firstly in animals (preclinical studies) and then in humans (stage I, then II, then III), where the number of volunteers and the costs involved increase with each stage. These phases are normally carried out sequentially, but the money available has allowed simultaneous testing. In order to do this, regulatory and surveillance capacities have been increased. The financial risks in case of failure were enormous, but without this massive injection of money there would have been no means of accelerating development.
- All these millions would have been spent uselessly if there had not been substantial research beforehand, which took time and which was in large part funded by public money. Years of virological research meant that there was already a great deal of knowledge about the family of coronaviruses (including SARS-CoV-1 and MERS). For example, the success of these vaccines depends on the fact that we know that SARS-CoV-2 mutates very little (unlike the flu) and doesn’t employ any particular strategy to outmanoeuvre our immune systems (unlike HIV or the herpes virus). And research on DNA/RNA vaccines began 25 years ago in the fight against cancer. Messenger RNA technology (mRNA) enables the production of vaccines more quickly and easily than with conventional vaccines. The first vaccine (Pfizer/BioNtech, USA / Germany) uses this technology, as does the Moderna vaccine (USA). The third approved vaccine came out of collaboration between AstraZeneca and Oxford University (UK) and uses the Adenovirus technology.
- To meet the challenge of this medical crisis, there has been collaboration between national and global infrastructures. For example, the CEPI (Coalition for Epidemic Preparedness Innovations) was created in 2017 to fight against the Zika virus, MERS and Ebola. It is funded partially by Moderna and Oxford, and provides a technological platform for the rapid development of vaccines. ICMRA (International Coalition of Medicine Regulatory Authorities) was created in 2012 and facilitates exchanges between national regulatory authorities to study side-effects.
Thus, several vaccines against SARS-CoV-2 were created in a year while most vaccines took years to develop.
This can be represented schematically as follows:
It seems unlikely that the levels of cooperation resulting from this unprecedented situation will apply to future vaccine development, but there are some benefits that could be permanent, and some lessons have been learned. The use of RNA vaccines, not authorized till recently, may enable the simple and rapid production of vaccines against other pandemics. Also, thanks to the data collected during the many clinical trials carried out in a single year, our understanding of immune responses to vaccines (in particular RNA vaccines) will have progressed more than in previous decades. Researchers are already working in anticipation of other pandemics, some of which might prove even more problematic than SARS-CoV-2. The extraordinary pace of the development of anti-COVID-19 vaccines (even though not all clinical testing has been completed) shows what medical science is capable of when supported. It should be underlined that in the future it would be judicious to use resources for prevention and / or surveillance of these viruses, rather than to urgently inject massive amounts of money when the epidemic arrives.