< Copaxone has been the best of the MS drugs for many years >
It is actually the weakest of the approved drugs (reduces relapses by 29%; never shown any disability progression benefit), and there is a Cochrane Medical review a few yeasr castijng doubt on it's efficacy for all but the most benign cases.
<As you suggest Tysabri may change that - it looks like it will be twice as effective>
Not "will be" - Tysabri cuts relapses by 68% almost 2.5x better), cuts disability progression by 50%, and sold $130m last q alone - it should do $750m this year, excluding Crohn's (just approved).
<Even Tysabri may yeald to Rituxan which on the surface looks about 50% more effective than Tysabri.>
You should look hard at your numbers - Rituxan was weaker than Tysabri on all counts (eg Rituxan cut relapses by 51% compared to 68%) in relapse-remitting MS (RRMS) which is 85% of all MS cases. In fact, DNA has already announced that development of Rituxan in RRMS has ceased. Its only chance now is in Primary Progressive MS, for whose patients there is nothing.
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