Postcode lottery for TNF-alpha in the UK

I think I'm beginning to understand the flurry of news stories from the UK that sound like adverts for TNF-alpha inhibitors (examples: 1, 2, 3). Rheumatology patients are encountering an unofficial "postcode lottery" -- i.e., a cap on the number of patients in a given locality who are able to receive the new treatments. Yes, they're expensive, but rationing seems cruel: either you have a national drug plan or you don't.