Hi Odette
Sorry to hear that your daughter is having such problems and understand your concerns. However in terms of self funding anti-tnf treatments are likely to be a 'no-go'. There are very strict NICE guidelines about the use of these drugs because they are extremely potent and very costly (approx £9000 a year depending which one is used).
Additionally, anti-tnf treatment is not for everyone and certainly age may be a consideration as the long term effects of these drugs are not yet widely known and she could be on these for life. When you say she has RA in her knee and both ankles alarm bells ring ... RA more usually affects the small joints of the hands and feet before moving into the larger joints. You don't mention fatigue or morning stiffness, very common symptoms of RA.
I think I would be inclined to ask for a second opinion before looking for more toxic medication. The anti-ccp test, done by a rheumatologist, will provide better evidence of the problems and should give a clearer indication when it comes to diagnosis. I assume only the Rheumatoid Factor has been checked (hence the sero-negative); this is not a definitive test for RA. If her disease is so severe at the outset she is likely to test positive to the anti-ccp. There are many different types of inflammatory arthritis and it isn't all RA. Two of my friends recovered completely after one flare each (granted they were uncontrolled for quite some time)!
There are numerous DMARDs available and it took me the best part of nine years to get through them all! I imagine there are others that she could try. Cimzia is not usually given as a first line anti-tnf drug anyway so it looks as though your PCT are looking for the cheapest option. The usual first choices are Humira, Enbrel or Infliximab.
I would suggest she sees a different rheumatologist and requests an anti-ccp test at the outset. Once this information is available it will give a fuller picture and consideration can be given to medication choice. Combination therapy of two or three DMARDS may be the way forward; methotrexate is usually the anchor drug with an additional one or two DMARDS thrown in.
Hope you find some resolution soon,
Lyn x