This vaccine was developed by Oxford University. AstraZeneca stepped in to produce it rapidly. They don't normally produce vaccines at all, but they do have very capable production facilities and people. In this case they committed to ramp up production several months in advance of the stage 2/3 results, because production ramp-up takes a long time and we really need a vaccine quickly. Yes, seems odd for big pharma to commit production resources with no prospect of big returns, but that's what they've done. Probably some of those production facilities were running under capacity anyway, as cancer treatments, etc have been postponed this year. I guess if it works, it will at least be a huge PR win, especially for their CEO who's gone out on a limb to make this happen.

https://www.bbc.co.uk/news/business-52917118