Finding a vaccine that protects us from the coronavirus is the first challenge.
The second challenge is getting a jab – or jab – widely available, worldwide, to allow returns to pre-COVID-19 normal conditions.
The main point:
- Most vaccine candidates can pass through existing transport systems
- Australia has signed an agreement to produce the Oxford / AstraZenica vaccine locally
- Some vaccine candidates need to be stored at subzero temperatures
Vaccine technology is intellectual property, meaning researchers need to undergo legal licensing procedures to partner with producers.
Queensland University biotechnology professor Linda Lua said the COVID-19 vaccine was not excluded from the process.
“The different vaccine technologies belong to the researchers,” said Professor Lua.
“[And] each vaccine will have a different setting depending on the country in which it is started. ”
Given the global implications of COVID-19, some researchers are licensing their vaccine technology to manufacturers around the world so that vaccines can be produced domestically to reduce the time, cost and risk of transport.
All vaccines must be transported through what is known as the “cold chain,” where vaccines remain refrigerated as they move through the various stages of delivery – from factories to ports, then to other countries and to clinics.
But many vaccines have special requirements for transport – some are very fragile and others must remain frozen – and in some cases, this requires expensive equipment.
Take for example the leading vaccines being developed in the US by Moderna and Pfizer / BioNTech – none of these are part of the current Australian Government vaccine plan as the local CSL producer does not have the technology to mass produce both vaccines in Australia.
Basically, scientists from both teams are trying to genetically engineer a harmless version of COVID-19 that triggers an immune response – think of it like 3D printing a synthetic model of the virus.
The man-made RNA (which viruses have in place of DNA) is coated with fat bubbles and then injected into the body.
Initial clinical trials provide “promising results”, however, it has been revealed that the fat bubbles protecting RNA must remain frozen during transport, or it will disintegrate.
For the Moderna vaccine, the temperature has to stay around -20C. For Pfizer, it’s more like -70C.
Once thawed, the Moderna vaccine can last for 14 days at normal refrigerator temperatures. For Pfizer, that’s five days.
But getting the vaccine to its location before this point is a logistical achievement in itself, particularly for the Pfizer / BioNTech vaccine.
“That one is a challenge in itself.”
Pfizer said it has developed its own thermal delivery box that can hold up to 5,000 doses for up to 10 days, company senior director Brian Gleeson said at a meeting at the Centers for Disease Control and Prevention (CDC).
But it is said that the container should not be opened more than twice a day or more than a minute at a time – that is, experts say, not quite time to sort through 5,000 doses.
The box needs dry ice to keep it cold – roughly 23 kilograms should be refilled within 24 hours of first opening the box, and then five days after that.
This presents a major challenge for rural and developing areas.
Australia supports more traditional vaccines
Australia has contributed $ 123 million to a global vaccine initiative, COVAX. Countries under the agreement are guaranteed access to certain supplies of nine COVID-19 vaccines, if they pass clinical trials.
If a successful vaccine requires two or more doses to be effective, the COVAX agreement may not provide all the doses Australia needs.
So countries including Australia are negotiating their own vaccine deals with individual producers to deal with such a scenario.
Australia has done this with the Oxford / AstraZeneca vaccine candidate – currently in phase 3 human trials – which uses a method known as a “virus vector”.
Viral vector methods place harmless viruses – in this case, common cold viruses – in dangerous suits, such as those that cause COVID.
The idea is that the body will put up a defense against what it perceives as COVID, without risking getting sick.
Melbourne-based vaccine manufacturer CSL has received funding from the Government to help it restructure its technology to produce vaccines locally if it passes Therapeutic Goods Association benchmarks for distribution.
It is understood that CSL plans to use the existing cold chain transport method used for the annual influenza vaccine – only on a larger scale – to transport the COVID vaccine across Australia from its manufacturing plant in Melbourne.
But for countries that do not have a domestic production agreement with AstraZeneca, the logistics of transport are not as robust as the frozen RNA vaccine.
Viral vector vaccines can be delivered in a cold state, usually around -2C, a temperature which is much easier to maintain.
Another local vaccine is the molecular clamp vaccine from the University of Queensland (UQ), which replicates the part of the virus that attacks cells in our bodies.
The idea is that by injecting the attacking parts without the coronavirus, it triggers an immune response without exposing the patient to the virus.
This the vaccine is in early phase 1 human trials.
A number of research facilities in China, such as Sinovac and Sinopharm, are also making progress with research using dead virus cells for vaccines, which are the most common type of vaccine.
The dead virus can no longer replicate and produce disease, but the presence of the virus itself triggers an immune response.
UQ and China-based vaccines can be transported using existing cold chain systems.
However, it is not completely seamless through this existing system. The number of doses required presents its own challenges.
“Of course mass, in terms of vaccine dosage, depends on how the pharmaceutical company is going to package it,” said Professor Lua.
A Health Ministry spokesman said it was working with medical facilities across the country to prepare for the launch of a COVID vaccine.
“The Ministry of Health is in constant contact with vaccine manufacturers regarding the transport and storage conditions for each COVID-19 vaccine.”