Ramanathan R, Biniwale M, Sekar K, et al. - In this multicenter, double blind, randomized, controlled clinical trial, researchers sought to compare safety and effectiveness of a new synthetic surfactant, CHF5633, enriched with surfactant proteins, SP-B and SP-C peptide analogues, with porcine surfactant, poractant alfa for the treatment of respiratory distress syndrome (RDS) in preterm infants. Preterm neonates on respiratory support requiring fraction of inspired oxygen (FiO ₂) ≥ 0.30 from 24 ^0/7 to 26 ^6/7 weeks and FiO ₂ ≥ 0.35 from 27 ^0/7 to 29 ^6/7 weeks gestation to maintain 88-95% oxygen saturation were randomized to receive 200 mg/kg of CHF5633 or PA. Redosing was given at 100 mg/kg if necessary. Of the 123 randomized neonates, 113 have been treated (56 and 57 in CHF5633 and PA groups, respectively). Treatment with CHF5633 in preterm neonates with moderate to severe RDS showed similar efficacy and safety as PA. Immunogenicity has not been observed.