Outcome after Selective early treatment for Closure of patent ductus ARteriosus in preterm babies, a multicentre, masked, randomised placebo-controlled parallel group trial (Baby-OSCAR trial).

Background: In extremely preterm babies, born before 28 weeks' gestation, a large (≥ 1.5 mm in diameter) patent ductus arteriosus present beyond 3 days of age is associated with higher mortality and morbidity than infants without a patent ductus arteriosus. The cyclooxygenase inhibitor ibuprofen may be used to treat patent ductus arteriosus. Whether selective early treatment of a large patent ductus arteriosus with ibuprofen improves health and developmental outcomes is not known. Methods: We conducted a multicentre, randomised, double-blind, placebo-controlled trial evaluating early treatment (≤ 72 hours after birth) with ibuprofen for a large patent ductus arteriosus in extremely preterm infants. The primary outcome was a composite of death or moderate or severe bronchopulmonary dysplasia at 36 weeks' of post menstrual age. The short-term secondary outcomes included complications of prematurity, patent ductus arteriosus closure and side effects of treatment. The main long-term outcome was survival without moderate or severe neurodevelopmental impairment, using parent report or classified by blinded end-point review committee at 24 months of corrected age. Other secondary outcomes included survival without respiratory morbidity and duration of oxygen supplementation. A health economic evaluation was undertaken. Results: A total of 326 infants were randomised to ibuprofen and 327 to placebo. The primary outcome occurred in 220/318 infants (69.2%) in the ibuprofen group and in 202/318 infants (63.5%) in the placebo group (adjusted risk ratio 1.09, 95% confidence interval 0.98 to 1.20; Conclusion: The risk of death or moderate or severe bronchopulmonary dysplasia at 36 weeks of post menstrual age was not statistically significantly lower for extremely preterm infants randomised to early treatment with ibuprofen compared to placebo. There was no evidence of an improvement in survival without moderate to severe neurodevelopmental impairment or survival without respiratory morbidity at 24 months' corrected age, after selective early treatment of a large patent ductus arteriosus with ibuprofen in children born extremely preterm. Future work: Future work required includes a trial in babies who are clinically symptomatic and fail to close the patent ductus arteriosus beyond 7 days of age; an individual patient data meta-analysis; follow-up of babies in Baby-OSCAR at 8-10 years of age. Limitations: Open-label therapy was received by 29.8% of infants in the placebo group, potentially increasing the percentage of infants with patent ductus arteriosus closure in this group. The first dose of trial treatment was administered at a median of 61 hours after birth, later than in other trials. Funding: This synopsis presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme as award number 11/92/15.