Safety and PK-PD Study of Oral L-CIT in Preterm Infants With BPD±PH and NEC

Arm 1: BPD±PH: Inclusion Criteria: * Born ≤ 30 weeks at birth * Post-menstrual age (PMA) ≥ 32 weeks * Echocardiographic evidence of PH for infants with BPD+PH. * On invasive or non-invasive ventilation with RSS \>2.0 for \>12hours/day for at least 48 hours as an early predictor of evolving BPD * Informed written consent (parents/substitute decision maker) Exclusion Criteria * Congenital Heart Disease \[Exceptions: small atrial septal defect (ASD), small ventricular septal defect (VSD), small patent ductus arteriosus (PDA)\] * Infants with pulmonary vein stenosis * Concurrent sepsis with hemodynamic instability * Infants considered likely to die within next 7 days * Any other condition that, in the opinion of the investigator, may adversely affect the infant's ability to complete the study or its measures or pose significant risk to the infant Arm 2: surgical NEC Inclusion Criteria: * Born ≤ 30 weeks at birth * Recovering from Stage IIIb NEC as per modified Bell's staging (pneumoperitoneum requiring surgery) * Tolerating 50 ml/kg/day of enteral feeds * Informed written consent (parents/substitute decision maker) * Considered medically stable by clinical team Exclusion Criteria * Congenital heart disease (except small ASD, small VSD and non hsPDA) * Pulmonary vein stenosis * Concurrent sepsis with hemodynamic instability * Likely to die within next 7 days * Other condition significantly affecting pulmonary function independent of prematurity or NEC