Tysabri Notes

Based on a teleconference witrh Carlo Tornatore, MD (Georgetown). He has experience with many patients with Tysabri and MS and has NIH research experience working with PML.
1. All patients have JC virus in their bone marrow. However, JC virus in the blood is abnormal and suggests an immunosuppressed state. (Test PCR either Athena or Mayo can be done at Quest labs). Patients with a negative JC virus may be eligible for Tysabri if they meet other criteria.
2. JC virus in blood along with MRI is repeated every six months. If postive, Tysabri is stopped. CSF can be checked and there "are no false positives in the CSF." If the PCR is positve they have PML. Generally CSF is checked if there is any question about a new lesion being PML.
3. PML (unlike NMO) does not affect optic nerves or spinal cord. Hypothesizes the oligodendrocytes are different.
4. Different cocktails for treating PML have been tried. Ara C is too toxic but a combination of alpha interferon, and sodafavir? is OK. The main thing is to stop the tysabri to reconstitute the immune system. To do so fully, he also phereses for 5 days followed by IVIG for five days.
5. He has 3 exacerbations in over 100 patients each treated for ?18 months. He used steroids for exacerbations.
6. Pretreat claritin and tylenol
7. jc virus pcr in blood helps if positive not if negative
8. take off tysabri if new lesions or if antibody positive
9. discounts rebound except after short term use
10. clinical trials good data both for newly diagnosed as well as breaking through
11. Work coming off on MR metrics, spectro, atrophy, vision
12. 9 % develop nabs but only 6 % have persistent ab's if persistent then stop drug (usually test after 6 months). Won't check again unless a clinical problem. Usually develop early. Athena or Focus labs. If someone is doing well with ab's.???
13. risk benefit is good in scenario of breakthrough disease
14. takes off platform therapy drugs for one month, 3 mo for other imm supp drugs prior to starting tysabri. Pulse steroids not a problem.
15. slightly increased infusion reactions in patients previously treated. NABs unknown