Doctor’s Note: Where are we in developing a coronavirus vaccine? | Coronavirus pandemic
Despite countries around the world taking differing approaches to manage the coronavirus, all of them agree on one thing: The only way out of this pandemic is to develop an effective vaccine.
How do vaccines work?
Vaccines generally work by injecting parts of a pathogen into the human body; these parts are called antigens as they are recognised as foreign by the body. Antigens are usually dead or weakened versions of the bacteria or virus itself, which then stimulate an immune response.
Antigens are not enough to make you unwell with the disease itself, but are sufficient for your body to recognise the pathogen as foreign and start producing immune cells that can destroy it.
Once they have destroyed the dead or weakened pathogen, some of these immune cells serve as memory cells or proteins that, if the real version of the illness is encountered, mount a much quicker immune response, destroying the pathogen before you feel unwell from it.
Developing a COVID-19 vaccine
Vaccines normally take years to develop. They go through rigorous testing procedures and large scale trials.
But the world is in desperate need of a vaccine for the coronavirus and more than 100 countries are now involved in fast-tracking research and trials in a race to produce an effective vaccine.
US and Europe
In mid-March, the first human trial of a vaccine to protect against the novel coronavirus pandemic started in the US. It was funded by the National Institutes of Health and is taking place in Seattle.
The trial aims to enrol 45 volunteers and inject them with a stable piece of genetic material from the SARS-CoV-2 virus (coronavirus) in varying doses, and will be carefully monitored over the coming months. The trial has sidestepped what is usually a vital part of developing a vaccine: animal trials. But the scientists have built the vaccine on previous knowledge of coronaviruses, such as the one that causes the severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS).
In April, the first European human trial of a potential coronavirus vaccine got under way. The vaccine was developed in less than three months by a team at Oxford University. More than 1,000 people will be recruited, half of whom will receive the SARS-CoV-2 virus vaccine while half will receive a widely available meningitis vaccine. Only the research team will know which vaccine has been given to each individual.
Again, part of the virus’ genetic code has been used to make the vaccine rather than the whole virus, and participants will be given varying doses and more than one vaccine; they will then be monitored for side effects and, more crucially, immunity.
Also in April, pharmaceutical giants Sanofi and GSK joined forces to develop a vaccine, something that they have described as “unprecedented”.
Sanofi will contribute its S-protein COVID-19 antigen, which they have stated is an exact genetic match for a protein found in the SARS-CoV-2 virus. GSK will contribute its “adjuvant” technology. Adjuvants are particularly important in vaccines as they accelerate, prolong, or enhance a person’s immune response when injected with a vaccine.
In this case, Sanofi has the genetic material from the coronavirus that will form the basis of their vaccine and GSK have the means to make that genetic material more effective, which is vital in a global pandemic.
Combinations of protein-based antigens and adjuvants are used widely in vaccines. Trials have already started and they are aiming to have an effective vaccine available by mid-2021.
They are not the only pharmaceutical companies throwing their hats into the ring in order to develop a coronavirus vaccine. Pfizer is collaborating with German-based company BioNTech, to use genetic material from the SARS-CoV-2 virus and develop a vaccine. Clinical trials are beginning in Germany and are hoped to extend to include the US in the future.
April was also the month that the World Health Organization (WHO) approved animal trials in Australia of a vaccine developed by Oxford University.
Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) says its tests will be the first comprehensive pre-clinical trials of the vaccines to use an animal model. They are using ferrets, one of the few animals known to contract the coronavirus in a similar way to humans.
China is also in the race to develop an effective vaccine. The company, CanSino Biologics, is building on its previous knowledge of virus proteins and vaccines to develop something it calls Ad5-nCoV. This is a harmless protein that will help carry a spike belonging to the coronavirus into cells, and cause an immune response that will mean immune cells develop to combat the SARS-CoV-2 virus.
It is now moving onto human trials, after apparent success in animal trials. This puts it ahead of its competitors. There are a number of other companies and organisations within China that are also developing their own vaccines.
At least a year away
Although the support that the development of these vaccines is getting from the WHO is unprecedented, it is important to know that most experts believe it will be mid-2021 before a vaccine becomes available, about 12-18 months after the new virus, known officially as SARS-CoV-2, first emerged.
This may seem far away, but it would be much quicker than any vaccine has been developed before. However, there is still no guarantee it will work.