Long-Term Follow-up Study for Patients From AVXS-101-CL-101

This is a long term, safety follow up study of patients in the AVXS-101-CL-101 gene
replacement therapy clinical trial for SMA Type 1 delivering AVXS 101. Patients will roll
over from the parent study into this long-term study for continuous safety monitoring for up
to 15 years. The last visit of the parent study or early discontinuation from the parent
study may serve as the visit at which the informed consent form process is conducted for the
AVXS 101 LT-001 long term follow-up safety study. Patients will return annually for follow up
study visits for five (5) years, and then will be contacted via phone annually for ten (10)
years. Additionally, patient record transfers from their local physician and/or neurologist
will be requested in conjunction with the annual study visits and phone contacts for review
by the investigator.

If the patient is unable to return to the original investigative site, the sponsor will
arrange with the patients' local established physician to serve as an additional investigator
to conduct the required assessments.

Inclusion Criteria:

1. Patient who received AVXS-101 in the AVXS-101-CL-101 gene replacement therapy clinical
trial for SMA Type 1.

2. Parent/legal guardian willing and able to complete the informed consent process,
comply with study procedures and visit schedule.

Exclusion Criteria:

1. Parent/legal guardian unable or unwilling to participate in the long term follow up
safety study.