Sinusoidal obstruction syndrome diagnosis and grading will use the European Society for Blood and Marrow Transplantation's Revised Diagnosis and Severity Criteria for Sinusoidal Obstruction Syndrome/Veno-Occlusive Disease in Adult Patients as published in 2016. Gradings are from mild to very severe (multi-organ dysfunction/multi-organ failure).

The American Thoracic Society Committee on Idiopathic Pneumonia Syndrome definition will be employed.

Oxalate nephropathy will be presumed if there is acute kidney injury or increased creatinine, grade 3 or higher by the criteria of CTCAE Version 5.0 within 48 h of the administration of vitamin C, in the absence of a clear alternative explanation (an example of an alternative explanation is tumor lysis syndrome).

Cytokine release syndrome will be assessed by the criteria of CTCAE Version 5.0. Elevation of plasma cytokine levels consistent with the diagnosis of cytokine release syndrome must be present.

Mucositis will be assessed using the WHO Mucositis Scale. Grading is from 0 (no symptoms) to 4 (no possible alimentation).

Neutrophil engraftment is defined as an absolute neutrophil count ≥ 500/microliter for 3 days, with the date of engraftment being the first of those 3 days. Delayed engraftment is engraftment that occurs after 21 days but within 30 days.

Neutrophil engraftment is defined as an absolute neutrophil count ≥ 500/microliter for 3 days, with the date of engraftment being the first of those 3 days. Failure to engraft within 30 days will be considered an engraftment failure.

Platelet engraftment is defined as a platelet count ≥ 20,000/microliter for 3 days, with the date of engraftment being the first of those 3 days. Delayed engraftment is engraftment that occurs after 30 days.

Adverse event is defined any untoward medical occurrence associated with the use of a drug in humans, whether or not considered drug-related.

An adverse event is considered serious if, in the view of either the investigator or Sponsor, it results in any of the following outcomes: * Death. * A life-threatening adverse event. * Inpatient hospitalization or prolongation of existing hospitalization. * A persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions. * A congenital anomaly or birth defect. Important medical events that may not result in death, be life-threatening, or require hospitalization may be considered serious when, based upon appropriate medical judgment, they may jeopardize the patient or subject and may require medical or surgical intervention to prevent one of the outcomes listed in this definition.

Grading will be measured using Common Terminology Criteria for Adverse Events version 5.0