Inclusion Criteria:

1. Male or female patients ≥ 18 years of age.
2. Patients with sporadic or familial amyotrophic lateral sclerosis (ALS) diagnosed as laboratory-supported possible, probable, or definite according to World Federation of Neurology El Escorial Criteria.
3. Pulmonary slow vital capacity (SVC) < 50% of predicted normal.
4. Must have a source of autologous T cells potentially sufficient to manufacture RAPA-501 cells, as defined by a peripheral CD3+ T cell count ≥ 500 cells per μl.
5. Patients who are taking riluzole (Rilutek), edaravone (Radicava), and/or sodium phenylbutyrate/taurursodial (Relyvrio) are eligible if taking the drug for at least 30 days prior to the screening visit.
6. Patients must be ≥ two (2) weeks removed from major surgery, or investigational therapy.
7. Patients must have no ongoing, unstable serious illness other than ALS, as determined by the Site Investigator.
8. Serum creatinine less than or equal to 2.0 mg/dL.
9. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 3 x upper limit of normal (ULN).
10. Bilirubin ≤ 1.5 (except if due to Gilbert's disease).
11. No history of abnormal bleeding tendency.
12. Voluntary written consent must be given before performance of any study related procedure not part of standard medical care, with the understanding that consent may be withdrawn by the patient at any time without prejudice to future medical care.

Exclusion Criteria:

1. Active uncontrolled infection.
2. Hypertension not adequately controlled by ≤ 3 medications.
3. History of documented pulmonary embolus within 6 months of enrollment.
4. Clinically significant cardiac pathology, as defined by: myocardial infarction within 6 months prior to enrollment, Class III or IV heart failure according to NYHA, uncontrolled angina, severe uncontrolled ventricular arrhythmias, or electrocardiographic evidence of acute ischemia or active conduction system abnormalities.
5. HIV, hepatitis B, or hepatitis C seropositive.
6. Pregnant or breastfeeding subjects.
7. Subjects of childbearing age, or males who have a partner of childbearing potential, who are unwilling to practice contraception.
8. Subjects may be excluded at the Principal Investigator discretion or if it is deemed that allowing participation would represent an unacceptable medical or psychiatric risk.

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 07/22/2024. Questions regarding updates should be directed to the study team contact.