The purpose of this study is to evaluate the safety and the tolerability of CL2020 cells in hypoxic ischemic encephalopathy neonates with hypothermia therapy. In addition, we will evaluate the efficacy of CL2020 cells for infant development.

Inclusion Criteria:

1. At least 36 weeks gestation, and either one of the following criteria (i.-iii.) i. Apgar score ≤5 at 10 minutes ii. Continued resuscitation for at least 10 minutes iii. pH <7.0 or base deficit ≥16 mmol/L in any blood sample obtained within 60 min of birth
2. Moderate or severe encephalopathy by a Sarnat criteria
3. Undergone therapeutic hypothermia started before six hours of birth, and done for 72 hours continuously
4. Birth weight ≥1,800 g
5. Heart rate ≥100/min, and SpO2 ≥90 %
6. Able to provide voluntary written consent after receiving adequate information about the study (consent will be obtained from an acceptable representative)

Exclusion Criteria:

1. Suspected or confirmed severe congenital abnormalities or chromosomal anomaly
2. Planned to undergo surgery or radiation therapy
3. Scheduled to take systemic corticosteroids treatment for over five days
4. Blood glucose ≥ 200 mg/dL
5. Participation in another clinical study (not exclude patients in observational studies)
6. Suspected or confirmed active and severe infection
7. Positive for HBs antigen, HCV antibody, HIV antibody, HTLV-1 antibody or syphilis serum reaction
8. History of severe hypersensitivity or anaphylactic reaction
9. Severe complications