Safety and Efficacy of APC-0101 in Preterm Infants With Respiratory Distress Syndrome

Inclusion Criteria: 1. Inborn at the study site's hospital (i.e., not transferred from another hospital following delivery) 2. Gestational age at birth of 26 through 33 weeks PMA 3. Birth weight appropriate for gestational age (AGA, weight 3rd to 97th percentile on Fenton Growth Curve) 4. Birth weight ≤ 2000 grams 5. Post-natal age 1 to 24 hours at randomization 6. On nCPAP or NIV for at least 30 minutes with RSS = 1.4 - 2.0 to maintain SpO2 90-95% at randomization. RSS is calculated as (nCPAP cm H2O) × (FiO2) or as (NIV mean airway pressure cm H2O) × (FiO2). 7. FiO2 ≥ 0.24 at randomization 8. nCPAP or mPaw ≥ 6 cm H2O at randomization 9. Chest radiograph (CXR) or lung ultrasound compatible with RDS prior to randomization Exclusion Criteria: 1. On SiPAP®, RAM® cannula, or high flow nasal cannula (HFNC) (\> 2 liters per minute \[LPM\]) at the time of randomization 2. Prior instillation of surfactant 3. Premature rupture of membranes (PROM) occurring \> 14 days before birth 4. Significant congenital/chromosomal anomaly (e.g., Pierre Robin syndrome, clinically significant congenital heart disease, or trisomy) 5. Pneumothorax 6. Other etiologies of respiratory distress 7. Enrollment in another interventional study with similar efficacy endpoints 8. Apgar score at 5 min of 0-3 9. Prior cardiopulmonary resuscitation (CPR) or epinephrine 10. Base Deficit \> 15 mEq/L on most recent arterial blood gas (not capillary blood gas, venous blood gas, or cord gas) prior to randomization. Note that arterial blood gas is not required prior to randomization. 11. Partial pressure of carbon dioxide (PaCO2) \> 65 mmHg on most recent arterial blood gas (not capillary blood gas, venous blood gas, or cord gas) prior to randomization. 12. Triplet or higher order multiple birth