Part of the NICE discussions is to apply pressure to get a lower price. I feel like this is a good thing to prevent gouging. The second version of the Cancer Drugs Fund is also useful here, because it makes available stuff that isn't in the BNF.
The draft guidance is here: https://www.nice.org.uk/guidance/ta567/documents/appraisal-c...
It's long and detailed and it'd be unfair of me to pull anything out specifically.