How should I transition from Tysabri to Ocrevus?

Here is My Question:
How should I transition from Tysabri to Ocrevus, now that it has been approved? I have been on Tysabri for over 6 years and am JC positive. I have been told by my neurologist that there is currently no information on how this transitions (e.g., time between infusions) should be safely accomplished. Any information appreciated.

Answer:
How to transition from Tysabri to Ocrevus depends on a number of circumstances:

1. If you are JCV antibody negative then your biggest concern is avoiding a relapse by waiting more than 3 months after your last Tysabri infusion to start Ocrevus. So you certainly want to start Ocrevus within  2 months of your last Tysabri infusion.
   
2. If you are JCV antibody positive and on Tysabri for more than 18 months, then your biggest concern is avoiding Ocrelizumab if you have early evidence of PML by MR imaging. In this case it is most prudent to obtain a repeat MRI of your brain  about 1 to 2 months after your last Tysabri infusion and before starting Ocrelizumab. If there are new abnormalities on the MRI that could be consistent with early PML, then you should have your spinal fluid analyzed (a lumbar puncture) before starting Ocrelizumab. As above, your goal is to start Ocrelizumab within 3 months of stopping Tysabri.

Revere (Rip) Kinkel MD
Professor of Clinical Neurosciences
Director of the Multiple Sclerosis Program
Clinical Neurosciences Director
University of California San Diego