The COVID19 spike sidles up to the ACE2 receptor, and when the spike docks, it changes shape. Many of the vaccines (Pfizer, Moderna, J&J) use a modification (the two proline, or 2P, modification) to the spike genome which holds the spike in the pre-docking shape, making the vaccine more effective. Well, the guy who invented 2P worked with some other people and figured out a six proline modification (called HexaPro) that makes the spike even more stable. This could go into any vaccine and make it better. Awesome.
Meanwhile, there is a research group which had been working to figure out how to grow vax in eggs. This is a relatively low-tech, very old way of growing vax. (It’s how they grow influenza vax, for example.) They figured out how to do that by adding spike protein genes to a harmless virus called the Newcastle disease virus.
They heard about HexaPro, and have use it instead of the original spike genome or even the 2P spike genome, et voilà, it works really well against COVID-19 in hamsters. They have licensed this to a number of vax makers, and a few have started trials.
This paper reports that two women who had allergic reactions to the Moderna vax were able to be given their second dose by giving them five smaller doses, gradually increasing the size of the doses.
Pfizer announced the six-months results from its long-term study, and found that there had been zero deaths or hospitalizations among those vaccinated. (Because it’s so new, we have no idea how long the protection lasts. We have to wait N months to see if protection will last N months.)
There is a new worrying variant out of India. (It doesn’t have a name or number yet.)