Multiple Doses of AT-1501-A201 in Adults With ALS

Open to people ages 18 years and up

1. ALS diagnosed as possible, laboratory supported probable, probable, or definite as defined by revised El Escorial criteria.
2. ALSFRS-R Aggregate score of 37 or greater
3. No more than 24 months from diagnosis.
4. Able and willing to give informed consent, follow trial procedures, and make multiple clinical site visits.

1. Any other central or peripheral nervous system disease that may interfere with the evaluation of ALS or its progression.
2. Presence of a tracheostomy, or use of permanent assistive ventilation (ventilatory support for 23 hours per day or more).
3. History of malignancy within the previous 5 years, except for localized non-melanoma skin cancers.
4. Abnormal function of the immune system resulting from:
5. Clinical conditions affecting the immune system (e.g. HIV infection, agammaglobulinemia),
6. Systemic administration of corticosteroids (PO/IV/IM) at a dose equivalent to 20 mg/day of prednisone for more than 14 consecutive days within 90 days prior to screening,
7. Administration of anti-neoplastic and/or immunomodulating agents (e.g. TNF α antagonists or anti-B cell antibodies) or radiotherapy within 1 year prior to screening.
8. Recipient of Stem Cell or Gene Therapy.
9. Positive test for Hepatitis B surface antigen, Hepatitis C antibody, or HIV.
10. History of deep venous thrombosis or pulmonary embolism.
11. History of active substance abuse within the past 2 years;
12. History of stroke, poorly controlled or significant cardiovascular disease, diabetes.