Experimental stem cells offered to kids with rare COVID complication

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria 1. 2 months to 17 years of age, inclusive 2. Positive for current or recent SARS-CoV-2 (COVID-19) infection by real-time reverse transcription polymerase chain reaction (RT-PCR), serology, or antigen test; or COVID-19 exposure within the 4 weeks prior to the onset of symptoms AND no alternative plausible diagnoses 3. Presenting with: * Fever (\>38.0°C or \>100.4°F for ≥24 hours) or reporting subjective fever lasting ≥24 hours * Laboratory evidence of inflammation with high sensitivity C-reactive protein (hsCRP) ≥4.0 milligrams per deciliter (mg/dL) and associated abnormalities of at least one of the following: * elevated erythrocyte sedimentation rate (ESR) * elevated fibrinogen * elevated procalcitonin * elevated d-dimer * elevated ferritin * elevated lactic dehydrogenase (LDH) * elevated interleukin 6 (IL-6) * elevated neutrophils * reduced lymphocytes * low albumin * Clinically severe multisystem illness requiring hospitalization with evidence for cardiac involvement plus at least one other organ involvement (renal, respiratory, hematologic, gastrointestinal, dermatologic or neurological) * Cardiac involvement is defined as reduced left ventricular ejection fraction (\<55%) in addition to at least one of the following: * increased troponin I, * increased N-terminal pro-B-type natriuretic peptide (NT-proBNP) or BNP and/or * echocardiographic and/or other imaging evidence of left anterior descending coronary artery (LAD) and/or right coronary artery (RCA) dilation associated with a z-score \> 2.5 4. If on mechanical ventilation or ECMO, ≤72 hours post initiation of the respiratory support device Exclusion Criteria 1. Documented other microbial cause for MIS-C including bacterial sepsis, staphylococcal or streptococcal shock syndromes, or infections associated with myocarditis such as enterovirus. Of importance, waiting for results of these investigations should not delay initiation of remestemcel-L therapy. 2. Females who are pregnant or lactating 3. Body mass index (BMI) ≥40 kilograms per square meter (kg/m\^2) 4. Known hypersensitivity to dimethyl sulfoxide (DMSO) or to porcine or bovine proteins 5. Aspartate aminotransferase/alanine transaminase (AST/ALT) ≥5x upper limit of normal (ULN) 6. Creatinine clearance \<30 mL/min 7. Serum creatinine \>2 mg/dL 8. Any end-stage organ disease which in the opinion of the treating physician may possibly affect the safety of the remestemcel-L treatment.