Isatuximab in Combination With Chemotherapy in Pediatric Patients With Relapsed/Refractory Acute Lymphoblastic Leukemia or Acute Myeloid Leukemia

Inclusion criteria:

* Participant 28 days to less than 18 years of age, at the time of signing the informed consent.
* Participants must have had a confirmed diagnosis of relapsed Acute Lymphoblastic Leukemia (ALL) of T- or B-cell origin including T-lymphoblastic lymphoma (LBL), or relapsed Acute Myeloblastic Leukemia (AML) including participants with history of myelodysplasia.
* Participants must have been previously treated for their disease and have relapsed or are refractory to most recent treatment. Participants in first or second relapse were eligible regardless of the remission duration.
* Participants who had no more than 1 prior salvage therapy.
* White Blood Cell (WBC) counts below 20 x10\^9/L on Day 1 before isatuximab administration

Exclusion criteria:

* Any serious active disease or co-morbid condition which, in the opinion of the Investigator, may interfere with the safety of the study treatment or the compliance with the study protocol.
* Participants must have been off prior treatment with immunotherapy/investigational agents and chemotherapy for \>2 weeks and must have recovered from acute toxicity before the first study treatment administration. Exceptions were participants who needed to receive cytoreductive chemotherapy in order to decrease tumor burden (the study treatment may have started earlier if necessitated by the patient's medical condition (eg, rapidly progressive disease) following discussion with the Sponsor).
* Prior stem cell transplant within 3 months and/or evidence of active systemic Graft versus Host Disease (GVHD) and/or immunosuppressive therapy for GVHD within 1 week before the first study treatment administration.
* Participants with LBL with bone marrow blasts \<5%.
* Participants with Burkitt-type ALL.
* Acute leukemia with testicular or central nerve system involvement alone.
* Participants who had developed therapy related acute leukemia.
* Live vaccine(s) within 30 days prior to the first IMP administration or plans to receive such vaccines during the study until 90 days after the last IMP administration.
* Participants with white blood cell count \> 50 x10\^9/L at the time of screening visit.
* Participants who had been exposed to anti-CD38 therapies within 6 months prior to Day-1.

The above information was not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.