UPDATE 21 April 2020
From today's Downing Street Press Briefing:
Oxford University researchers will begin human trials of a potential vaccine on Thursday, says Health Secretary Matt Hancock. (1)
The Jenner Institute (University of Oxford) and the Oxford Vaccine Group are developing a vaccine that targets the club-shaped spikes seen on the surface of the virus.
Researchers have isolated the genetic code of these surface spikes and have been able to attach that code to a known harmless virus which then starts to make the spikes itself. This forms the basis of the vaccine and once injected into the body the immune system believes it is the genuine coronavirus and attacks it.
Whilst any news on a potential vaccine is a cause for optimism it must be remembered that the testing of any new drug or vaccine in humans takes time. This vaccine will be given to healthy volunteers first to assess primarily its safety rather than if it works (its efficacy) although scientists will continually be trying to assess efficacy. This is the Phase I trial. If it appears safe Phase II begins where it is given to a wider selection of people to continue to assess its safety across variables such as age and underlying conditions and look deeper into its efficacy. In Phase III it is rolled out to thousands of people to continue to evaluate both its safety and efficacy and, if no problems are found, this phase will end with it being licenced for general use. The final phase, Phase IV, is the ongoing monitoring of the vaccine after it has been licenced. From the beginning of Phase I until the end of Phase III normally takes years, not months. However under the current circumstances researchers are working hard to speed the process up as much as possible without compromising safety. The team working on this under Professor Sarah Gilbert have already developed a ground breaking vaccine for the coronavirus that causes Mers-Co (you can read more on Mers-Co here) which puts them in an ideal position to do this again. (2)
Original Piece 6 April 2020
There are currently 47 trials researching a possible vaccine for COVID-19. Most of these trials are in the pre-clinical stage (not yet being tested in humans) but four are now in the clinical stage (being tested in humans).
The process from beginning to end usually takes a minimum of six to seven years.
With COVID-19 the timeline is being measured in months with scientists around the world working to create a safe and reliable vaccine against the clock.
A new illness presents many challenges in the search for a vaccine. To create a vaccine the virus itself has to be fully understood first; its genetic make-up, its behaviour and its degree of infectivity.
The most common way to make a vaccine is to use an inactivated version of the virus known as the antigen. The antigen is created by weakening and inactivating the virus through chemical processes. The virus antigen is then grown, often in eggs (which is why people are asked if they are allergic to eggs prior to vaccination). When the antigen is introduced into the body via vaccination there is no live virus to cause the actual illness but the antigen is sufficiently similar to the original virus that the body mounts an immune response and develops antibodies against it. As and when the person comes into contact with the actual virus the body is able to fight it off with these antibodies.
The arduous process of clinical trials must be followed even during a pandemic. A vaccine cannot be made and rolled out to the populous until scientists know that it is working, it is safe and its effects last for a long enough period of time for the outbreak of disease to end. A safe vaccine that kills the virus but only gives a month’s immunity would serve very little purpose. Vaccines vary in how long they last which is why some are given only once or twice in a lifetime and others must be re-administered, or boosted, every few years.
In a pandemic such as the current COVID-19 outbreak scientists work to fast track the whole process but without curtailing any part of the clinical trial.
So, how long will it be before there is a vaccine for COVID-19? There is no accurate answer to that question as realistically, even with a much speeded up process, it could be 12 to 18 months. However there is a possibility that a new process could change that. Vaccine technology is moving on apace and one of the current trials is using a different process altogether to the antigen process described above.
Inside the virus causing COVID-19 is a substance called RNA which houses the virus’s genetic code. By isolating the genetic code of the virus, and using that as the vaccine, you have all the information needed for the body to mount an immune reaction without needing to grow the antigen within eggs. The vaccine currently being manufactured with this new technique by US drug company Moderna started testing in humans on March 16th 2020. If it stands up to scrutiny in the human trials it is possible that it could be released in autumn 2020.
For those wanting to understand more about the process this is an excellent article:
In the meantime trials using antigen based technology are continuing alongside Moderna’s work.
https://www.statista.com/statistics/1106306/coronavirus-clinical-trials-worldwide/
https://patient.info/news-and-features/covid-19-coronavirus-when-will-we-have-a-vaccine
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