Study of Blinatumomab Administration in Chinese Pediatric Participants With Relapsed/Refractory B Precursor Acute Lymphoblastic Leukemia (R/R B-ALL)

Inclusion Criteria:

• Participant's parent or legally authorized representative has provided informedconsent when the participant is legally too young to provide informed consent andthe participant has provided written assent based on local regulations and/orguidelines prior to any study-specific activities/procedures being initiated

• Pediatric participants aged > 1 month and < 18 years at the time of informed consent

• Relapsed or/refractory precursor B-cell acute lymphoblastic leukemia (ALL) disease,defined as ≥5% bone marrow blasts with at least one of the following:

• Second or later bone marrow relapse;

• Any marrow relapse after allogeneic hematopoietic stem cell transplant (alloHSCT);

• Refractory to other treatments:

• For participants in first relapse: failure to achieve a complete remission (CR)following a full standard reinduction chemotherapy regimen

• For participants who have not achieved a first remission, failure to achieveremission following a full standard induction regimen

• Karnofsky performance status ≥ 50% for participants ≥ 16 years

• Lansky performance status ≥ 50% for participants < 16 years

Exclusion Criteria:

• Evidence of current central nervous system (CNS) involvement by ALL. Participantswith CNS disease at the time of relapse are eligible if CNS is successfully treatedprior to enrollment.

Other Medical Conditions

• Clinically relevant CNS pathology requiring treatment (eg, unstable epilepsy).

• Isolated extramedullary (EM) disease.

• Active malignancy other than ALL.

• Burkitt's leukemia according to the World Health Organization (WHO) 2016 criteria.

• Abnormal renal or hepatic function at screening as defined below:

• Abnormal serum creatinine based on age/gender as described by Threshold CreatinineValues

• Direct bilirubin > 1.5 mg/dl (25.6 μmol/L) at screening (unless related to Gilbert'sor Meulengracht disease).

• Symptoms and/or clinical signs and/or radiological and/or sonographic signs thatindicate an acute or uncontrolled chronic infection, any other concurrent disease ormedical condition that could be exacerbated by the treatment or would seriouslycomplicate compliance with the protocol.

• Known infection with human immunodeficiency virus (HIV) or chronic infection withhepatitis B virus (hepatitis B surface antigen [HBsAg] positive) or hepatitis Cvirus (HCV) (anti-HCV positive).

• Known hypersensitivity to blinatumomab or any of the products or components of theblinatumomab formulation.

Prior/Concomitant Therapy

• AlloHSCT within 12 weeks prior to start of protocol-specified therapy.

• Active acute or chronic Graft-versus-Host-Disease (GvHD) requiring systemictreatment with immunosuppressive medication.

• Radiotherapy within 2 weeks prior to start of protocol-specified therapy.

• Immunotherapy (eg, rituximab) within 4 weeks prior to start of protocol-specifiedtherapy. Prior failed cluster of differentiation 19 (CD19) directed therapy such asprior blinatumomab or CD19 chimeric antigen receptor T cells (CAR T cell) will beallowed (with demonstrated continued CD19+ expression) if treatment ended > 4 weeksprior to start of protocol-specified therapy.

• Cancer chemotherapy within 2 weeks before the start of protocol-specified therapy.With the exception of intrathecal chemotherapy and/or low dose maintenance therapyfor example vinca alkaloids, mercaptopurine, methotrexate, or hydroxyurea orpre-phase chemotherapy and/or dexamethasone. Any low dose chemotherapy as statedabove must be discontinued before starting pre-phase.

Prior/Concurrent Clinical Study Experience

• Currently receiving treatment in another investigational device or drug study, orless than 4 weeks since ending treatment on another investigational device or drugstudy(ies). Other investigational procedures while participating in this study areexcluded.

Other Exclusions

• Female participants of childbearing potential with a positive pregnancy testassessed at Screening by a highly sensitive urine or serum pregnancy test.

• Female participants who are breastfeeding or who plan to breastfeed while on studythrough 12 months after the last dose of protocol-required treatment with highestteratogenic risk.

• Female participants of childbearing potential unwilling to use protocol-specifiedmethod of contraception during treatment and for an additional 12 months after thelast dose of protocol-required treatment with highest teratogenic risk.

• Male participants with a female partner of childbearing potential who are unwillingto practice sexual abstinence (refrain from heterosexual intercourse) or usecontraception during treatment and for an additional 6 months after the last dose ofprotocol-required therapy with highest teratogenic risk.

• Participant likely to not be available to complete all protocol-required studyvisits or procedures, and/or to comply with all required study procedures to thebest of the participant and investigator's knowledge.

• Female participants planning to become pregnant while on study through 12 monthsafter the last dose of protocol-required treatment with highest teratogenic risk.

• Male participants unwilling to abstain from donating sperm during treatment and foran additional 6 months after the last dose of protocol-required treatment withhighest teratogenic risk.