Overview of clinical trials comparing natural and synthetic surfactants

This overview summarizes the ten randomized clinical trials that have compared different surfactant preparations. Six trials, enrolling 2,450 babies with respiratory distress syndrome (RDS), compared Survanta and Exosurf. Babies treated with the natural surfactant had lower oxygen requirements for at least 3 days than those treated with the synthetic surfactant. The babies treated with Survanta had lower risks of neonatal mortality (odds ratio, OR, 0.80; 95% confidence interval, CI, 0.65-1.00), retinopathy of prematurity (OR 0.68; 95% CI 0.50-0.94), and death or bronchopulmonary dysplasia (OR 0.84; 95% CI 0.70-1.00) when compared to those treated with Exosurf. Infasurf has been compared with Exosurf in two studies: one as prophylaxis and the other a rescue trial. Similar, although non-significant benefits were found for the natural surfactant. When all eight trials were included in a meta-analysis, there was a significant reduction in the odds of pulmonary air leaks (OR 0.52; 95% CI 0.41-0.66) for babies treated with natural as compared with synthetic surfactants. For seven trials (3,576 babies) comparing natural and synthetic surfactants to treat RDS (six comparing Survanta and Exosurf and one Infasurf and Exosurf), there was a significantly reduced risk of neonatal mortality (OR 0.80; 95% CI 0.66-0.97) with natural as compared with synthetic surfactant treatment. In two further trials different natural surfactant preparations have been compared. Reduced oxygen needs for 24 h after treatment were found for Infasurf and Curosurf, respectively, when compared to Survanta. Apparent longer-term benefits from these surfactants were not statistically significant. Further trials are needed to be certain of the differences between various surfactant preparations.