Cov 19 Vaccine numbers.

[Professor]

Another quick one for Prof...

When you upscale vaccine volume, do you just ratio the ‘recipe’ or do you have to modify?

Now that’s actually a complex question- as vaccine types vary. The Oxford vaccine is a live vector. A chimpanzee adenovirus (a type of cold) that has been made less virulent. The spike protein gene from SARS CoV2 has been incorporated so the protein is produced (or expressed) by this virus. We grow the virus in cells (in huge quantities) which is harvested and usually added to carrier solvent and some preservative. So it’s easy to scale up.

The Pfizer vaccine is made of mRNA so is harder to make. Either has to be chemically synthesised or uses polymerase enzymes to transcribe from a DNA template. What else is in this I am not sure. It may have a compound called an adjuvant which helps stimulate immunity. These are more common in vaccines that are not live. The regulators will know but may be protected IP. Generally it is cheaper to make live vaccines as the viruses or bacteria grow in big numbers. But there are more risks. So, no the composition won’t change, just the scale of production. If you ever go
Liverpool airport you can see the AZ flu vaccine facility near the Jaguar Land Rover Works. It is big.