SPEARHEAD-3 Pediatric Study

This is a pediatric basket study to investigate the safety and efficacy of afamitresgene autoleucel in HLA-A*02 eligible and MAGE-A4 positive subjects aged 2-21 years of age with advanced cancers

Inclusion Criteria:Age 2-21 yearsBody weight ≥ 10 kgSubject has histologically confirmed diagnosis of any one of the following cancers: (A) Synovial Sarcoma, (B) MPNST, (C) Neuroblastoma, or (D) OsteosarcomaMust have previously received a systemic chemotherapyMeasurable disease according to RECIST v1.1 (or INCR, 2017 Neuroblastoma only).HLA-A*02 positiveTumor shows MAGE-A4 expression confirmed by central laboratory.Performance Status: ECOG 0-1 or Lansky Score ≥ 80Exclusion Criteria:HLA-A*02:05 in either allele; or any A*02 having same protein sequence as HLA-A*02:05History of allergic reactions attributed to compounds of similar chemical or biologic composition to fludarabine, cyclophosphamide.History of autoimmune or immune mediated diseaseKnown central nervous system (CNS) metastases.Other prior malignancy that is not considered by the Investigator to be in complete remissionClinically significant cardiovascular diseaseActive infection with human immunodeficiency virus, hepatitis B virus, hepatitis C virus, or human T cell leukemia virusPregnant or breastfeeding