To assess the role of inhaled nitric oxide (iNO) in reducing the need for oxygen therapy, decreasing time on mechanical ventilatory support, and attenuating probability of hypoxic respiratory failure severity progression, we reviewed published reports of phase III iNO studies in neonates with hypoxic respiratory failure and pulmonary hypertension, as well as a novel post-hoc analysis of data from the Clinical Inhaled Nitric Oxide Research Group Initiative (CINRGI) study population not been previously reported. The post-hoc analysis of the CINRGI study showed that iNO shortens the duration of oxygen therapy versus placebo (17 vs. 34 days; P<0.05); the CINRGI retrospective analysis by Konduri et al. showed earlier administration of iNO (oxygenation index [OI] 15-25) yielded a 48% relative reduction vs. placebo in number of patients who progressed to OI≥30 (16.7% vs. 32.2%; P=0.002). Golombek and Young's pooled analysis of phase III studies showed a rapid improvement in oxygenation after initiation of iNO therapy versus controls in each study, and a significant reduction in median ventilation duration (11 vs. 14 days; P=0.003). A study by Gonzalez et al. revealed that earlier iNO administration in infants with mild to moderate hypoxic respiratory failure (OI 10-30) resulted in a decreased duration of oxygen therapy versus placebo (11.5 vs. 18.0 days; P<0.03) and reduced the probability of developing severe hypoxic respiratory failure.