Spearhead 1 Study in Subjects With Advanced Synovial Sarcoma or Myxoid/Round Cell Liposarcoma

Key Inclusion Criteria

• Age ≥16 (10 years at selected sites) and <=75 years

• Diagnosis of advanced synovial sarcoma (Cohort 1, Cohort 2 and Cohort 3) or myxoidliposarcoma / myxoid round cell liposarcoma (Cohort 1 only) confirmed bycytogenetics.

• Previously received either an anthracycline or ifosfamide containing regimen.

• Measurable disease according to RECIST v1.1 prior to lymphodepletion

• HLA-A02:01, HLA-A02:02, HLA-A02:03 or HLA-A02:06 positive

• Tumor shows MAGE-A4 expression confirmed by central laboratory. North America Only (United States and Canada): Tumor (either an archival specimen or a fresh biopsy)shows MAGE-A4 expression of ≥1+ staining in ≥10% of the cells byimmunohistochemistry.

• ECOG Performance Status of 0 or1. For subjects aged ≥10 to ≥16 years old:

Lansky Score ≥60%.

• Left ventricular ejection fraction (LVEF) ≥50%.

Note: other protocol defined Inclusion criteria may apply

Key Exclusion Criteria:

• HLA-A*02:05 in either allele

• Received or plans to receive the following therapy/treatment prior to leukapheresisor lymphodepleting chemotherapy: Cytotoxic chemotherapy, Tyrosine kinase inhibitor (TKI) (e.g. pazopanib), Immune therapy (including monoclonal antibody therapy,checkpoint inhibitors,), Anti-cancer Vaccine, Gene therapy using an integratingvector (subjects who have received a gene therapy using a lentiviral vector may beeligible for the study), Corticosteroids or any other immunosuppressive therapy,Investigational treatment or interventional clinical trial, Allogeneic hematopoieticstem cell transplant, Radiotherapy to the target lesions, Major surgery

• History of allergic reactions attributed to compounds of similar chemical orbiologic composition to fludarabine, cyclophosphamide or other agents used in thestudy.

• History of autoimmune or immune mediated disease

• Symptomatic CNS metastases including leptomeningeal disease.

• Other prior malignancy that is not considered by the Investigator to be in completeremission

• Clinically significant cardiovascular disease

• Uncontrolled intercurrent illness

• Active infection with human immunodeficiency virus, hepatitis B virus, hepatitis Cvirus, or human T cell leukemia virus

• Pregnant or breastfeeding

Note: other protocol defined Exclusion criteria may apply.