Quite interesting that, according to
How to vaccinate the world (essential listening IMHO), the EU approached the vaccine production in its normal way, tendering and using it's economic clout to lower costs while the UK just basically bought everything they could get their hands on whatever the price and no tenders required.
Which is basically what the Johnson's Government do. Seems to have worked in this case.
Also interestingly after all the complaining and jeering from Brexiteers about the EU threatening export controls on vaccines, the UK has been doing just that on PPE from the start of the pandemic.
Stephen