I'm an immunologist, I don't work on vaccines but I'll give you...

I'm an immunologist, I don't work on vaccines but I'll give you my 2 cents....the UoQ vaccine uses a protein clamp technology that stabilises the spike protein from Covid (the target used to train the immune system). This is a new technology, the more stable the vaccine target protein, the better the vaccine basically. This technology can be used with any protein clamp. They used HIV because it showed the best stability and because their system was also set up with it...if they had chosen new clamp proteins it would have delayed the vaccine development substantially. In normal times this would have been fine but given the global pandemic, they kept with the HIV clamp and mutated the known antibody binding points used for the HIV diagnostic test. Unfortunately there looks like there was some cross-reactivity. Its a real shame, but this is the way science works. This is why most new drugs are canned during development.