At university, I studied a module entitled ‘Chemical Pharmacology’, the science of the development of drugs. The lecturer used his very first slide to illustrate the importance of drugs in treating human health: a graph of the death rate in England over the past few hundred years which showed a gentle downward trend, marked by two significant, if lengthy, dips. The lecturer explained that those dips were caused by improvements in public hygiene in the 19th century and the general introduction of vaccines in the 20th century. No other factors, such as antibiotics or the battle against cancer, had any noticeable impact…
This lengthy preamble is to demonstrate that vaccines have been by far the biggest (and arguably only significant) innovation in public health and well-being.
Vaccines: A short history
Edward Jenner is rightly famous for his innovative contribution to immunization and the ultimate eradication of smallpox, although there is evidence that the Chinese used a similar process a thousand years earlier. Since Jenner’s time, vaccines have been developed against rabies, diphtheria, tetanus, anthrax, cholera, plague, typhoid, and tuberculosis. In the last century, new technologies allowed vaccines to be produced against polio, measles, mumps, and rubella, and vaccines against childhood illness have dramatically reduced the burden of these diseases.
How do vaccines work?
Vaccines work by stimulating the immune system against specific parts of a disease-causing agent, so that when the infectious agent is encountered ‘in the real world’ then the immune system is triggered to make a powerful response.
The initial vaccine can use a fragment of the infectious organism, an inactivated or killed organism, or a version genetically modified to be non-infectious. In fact, vaccines are not particularly difficult to make but can be extremely expensive to test, requiring a mass-vaccination campaign to compare disease incidence between vaccinated and non-vaccinated subjects. And of course, safety issues become paramount as the balance of population safety versus individual harm needs to be carefully weighed.
Can we expedite the delivery of vaccines?
From the discovery of SARS-CoV-2, we have now generated over 100 vaccine candidates in about 9 months, with 45 vaccines already in clinical trials. Realistically, completion of Phase 3 trials will take another 6 months. Only one vaccine has been given regulatory approval, Russia’s Sputnik-V, and that has not been through Phase 3 trials.
The scientific community has demonstrated an extraordinary capacity for innovation to explore new approaches to vaccine development, and the sheer variety in approaches could serve us well in future outbreaks of other novel diseases. These approaches include DNA vaccines, mRNA vaccines, vaccines based on other viruses, and other completely novel technologies
Meeting the challenges through innovation
But the most difficult part of creating a vaccine is its manufacturing: manufacturers will need to make hundreds of millions of doses of vaccine using perhaps unproven technology while competing for critical supplies such as glass vials. The average time to develop a vaccine is normally several years, but during the pandemic, vaccine developers have condensed this process into a matter of months. In practice, this requires several stages of development to be carried out in parallel and manufacturing to be done ‘at-risk’ without foreknowledge of the vaccine efficacy. Not only does this require innovation in technology but also innovation in the ways projects are managed, handled, and assessed.
And then there is distribution. Matt Hancock has suggested that the UK is ‘likely’ to have a COVID-19 vaccine by early 2021, but even if that were so there remain huge problems in distribution. The UK is fortunate that the NHS has an infrastructure for mass-vaccination, as seen with seasonal flu, but other countries may not be so capable. Can we develop innovative ways of delivering vaccines, perhaps by recruiting and retraining healthcare staff, or can we develop novel auto-injection systems that do not require healthcare workers?
The current COVID-19 pandemic has presented a huge challenge to society. Largely this challenge has been met so far through incredible displays of dedication by healthcare workers, but to move beyond the pandemic we will have to embrace new technologies and new ways of working. Innovation will need to be core to our thinking and our behaviours if we are to restore our economy and our society.