I understand your dilemma and how you are feeling. I have been unable to take betaseron, copaxone, and tysabri due to allergic reactions, infusion reactions, and the development of antibodies. I know that I may have to consider chemo or a clinical trial at some point. Lots of people seem to be having luck with tysabri. I hope your insurance approves it quickly and that your experience with tysabri is a positive one.