A Single-Arm, Open-Label, Multicenter, Phase 1b/2 Study Evaluating the Safety and Efficacy of AUTO1 (obecabtagene autoleucel [obe-cel]) in Pediatric Patients with CD19-positive Relapsed/Refractory (R/R) B cell Acute Lymphoblastic Leukemia (B ALL) or R/R Aggressive Mature B Cell Non–Hodgkin Lymphoma (B NHL)

Prior treatment

• Prior CD19 targeted therapy other than blinatumomab.

Other illness

• Active CNS involvement by malignancy, defined as CNS-3 per pediatric NCCN Guidelines. Note: Individuals with a history of CNS disease that has been effectively treated to CNS1 or CNS2 status at the time of enrollment will be eligible
• Presence of active or uncontrolled fungal, bacterial, viral, or other infection requiring systemic antimicrobials for management.
• History or presence of active or latent Hepatitis B virus or active Hepatitis C virus.
• History of human immunodeficiency virus (HIV), human T cell lymphotropic virus (HTLV)-1, HTLV-2, or syphilis positive test.

Other

• Chronic myelogenous leukemia lymphoid in blast crisis.
• History or presence of clinically relevant CNS pathology
• Patients who have experienced ≥ Grade 3 neurotoxicity following blinatumomab.

• Males or females < 18 years old at screening
• ≥ 6 kg body weight at screening
• Willing and able to give written, informed consent to the current study (participant and/or parent or legal guardian).
• Agreement to have a pregnancy test and use adequate contraception (if applicable).
• Participants with a diagnosis of r/r CD19-positive B ALL defined as one of the following sub-categories: (1) Primary refractory (2) First relapse (3) Second or greater relapse (4) Relapsed or refractory disease post-allogeneic stem cell transplant (5) Philadelphia chromosome-positive (Ph+) ALL. All B ALL participants enrolled during the Phase 2 portion of the study must meet a disease status, documented at screening per NCCN Guidelines: Pediatric ALL definitions for r/r pediatric B ALL
• Karnofsky (age ≥ 16 years) or Lansky (age < 16 years) performance score ≥ 50.
• For individuals with B ALL, documentation of CD19 expression on leukemic blasts in the BM, peripheral blood or cerebrospinal fluid (CSF), or biopsy no more than 30 days prior to consent. In participants treated with blinatumomab, testing should be undertaken after blinatumomab therapy has been stopped. In participants with mature B NHL, CD19 expression must be confirmed in a biopsy after any CD19-targeting therapies.