A handful of patients (2?) have undetectable viral loads after being treated for leukemia. In these cases, the bone marrow or stem cells were from donors with a mutation in CCR5 that confers some resistance to HIV. The mechanism isn't completely understood, AFAIK, since people with the CCR5 delta32 mutation have partial, but not complete, resistance to HIV normally.
It's not a very viable treatment yet: the transplant procedure is brutal (a friend went through it) and you need to be unlucky enough to need a transplant, yet lucky enough to find a donor that has the right mutations (which again, are not completely known) AND is otherwise compatible with the patient.
Still, very exciting for a possible mechanism, but also probably not coming to a hospital near you this decade.
Here's one of the studies: https://www.nejm.org/doi/10.1056/NEJMoa0802905
The short answer is that there is a bunch of different types of vaccines, and each type has different constraints on their production. Someone who makes an mRNA vaccine isn't going to be able to easily switch to making a live attenuated vaccine instead, for example. Also, first does not necessarily mean best: again, with so many approaches, a vaccine using a different approach can have wildly different side-effects and risk factors. So being second (or even, say, tenth) isn't necessarily a loss.
That said, there are so many projects pushing forward that many of them are bound to fail early. Given the history of cooperation already in this crisis, some of those companies who find their coronavirus vaccine efforts going up in smoke may well choose to help scale out other, more successful efforts--or instead help by taking on more of the current vaccine production efforts, as polio and the flu aren't going away just because coronavirus is here.
Vaccination on large scale will likely require tens of millions of doses, if not more (and let's not forget you may need more than one inoculation).
The economic benefits to distributing a vaccine quickly would be huge, but I haven't heard world leaders talking about how to do it--they're still on the last war. Luckily, Bill Gates is spending on it, but this needs way more attention because this is our chance to be ahead of the virus for once.
https://www.weforum.org/agenda/2020/04/bill-gates-7-potentia...
That wouldn’t even be enough to vaccinate a mid sized EU country.
'The vaccine could come from anywhere. We've got a domestic vaccine discovery programme in the UK which is being supported, absolutely, as fast as we can go, but the vaccine can come from anywhere. GSK and Sanofi have announced they're doing a vaccine together, which is fantastic news. Most of the big companies are doing vaccines. This is going to come from somewhere, we just need to back lots of horses at the moment, and to make sure we're in a great position to access a vaccine when it occurs. And that's why organisations like CEPI are so important as well; to make sure that the world sees this as a way to get a vaccine, and we all need to be part of the same approach to trying to get as many vaccines as we can. And we may need more than one vaccine.'
Link to the press conference: https://youtu.be/jWOCpmjdHiw?t=1430
Some other comments have referred to the Gates Foundation's contribution to developing vaccines; the foundation's involvement in establishing CEPI (the Coalition for Epidemic Preparedness Innovations), which Vallance referred to, is a significant part of this.
Multiple different vaccines could (and probably will) be discovered. These may have different mechanisms and tradeoffs and those too will be taken into account when scaling up to population.
Now who owns what, who gets it first, and who gets paid and in what way, those are thorny issues that have not yet been worked out.
This is a government funded university project, so "losing the race" is likely not a primary concern; I'm sure if someone else came out with a magic vaccine fully tested and ready to mass manufacture tomorrow the researchers on this project would be pretty happy about that.
Likely all of them would be developed anyway as some might end up failing (either during testing or during mfr) and I imagine demand is going to be high.