I agree with BillyLitt about the mouse proteins. I think that makes a big difference. I had a reaction of hives with the Remicade but never had any ill reactions to Humira. It didn't really work :-(, but I had no adverse reactions!
--40 year old female, dx as UC in '04 (1st symptoms in '03), switched to Crohn's in '05, 1 fistula, crohn's colitis, limited to large intestine
--rejected (reaction/didn't work): Asacol, AZA, 6-MP, MTX, Remicade, Humira, prednisone
--stuck on methylprednisolone, tried Prochymal in Phase III study (can't wait til it's approved!)
--started Tysabri 3/21/08
--single mom to 10-year-old girl