Starting Fayuvi (rebisufligene etisparvovec-hopf)Your first 90 days with sanfilippo syndrome type A: the steps, the dates and who to call

How you take it

One infusion into a vein, given once at a hospital trained in gene therapy. It takes about 1 hour, and your child takes a steroid by mouth for at least 12 weeks around it, counting the slow step-down at the end.

Before your first dose

• A test that proves your child has Sanfilippo type A, either a gene test or an enzyme test.
• A blood test for antibodies against AAV9, the virus shell that carries the new gene. If the level is too high, Fayuvi is not recommended.
• Blood tests of your child's liver, platelets and clotting, and a check that any infection is under control.
• No vaccines in the 30 days before treatment or while your child takes the steroid. Ask your pediatrician how to fit regular shots around it.
• You enroll in UltraCare, the support program run by the drugmaker. A Guide checks your insurance and follows up on any appeal.
• A date at a Qualified Treatment Center, one of the hospitals in the drugmaker's network trained to give gene therapy.

The first 90 days

1. Weeks beforeDiagnosis papers and the AAV9 antibody test
2. Once referredUltraCare enrollment and insurance
3. 30 days beforeNo vaccines from here until the steroid ends
4. Week beforeBaseline blood tests and weight
5. Day beforeThe day before, the daily steroid starts
6. Day 1The infusion
7. Day 8Week 1 blood tests
8. Day 15Week 2 blood tests
9. Day 22Week 3 platelet count
10. Day 29Week 4, the last weekly platelet check
11. Day 43Liver tests, every 2 weeks
12. Week 8Week 8, the doctor decides when to lower the steroid
13. Week 12 or laterEarliest end of the steroid taper
14. About 3 monthsAbout 3 months, extra diaper and hand washing care ends