Objective To conduct an economic evaluation alongside the placebo-controlled trial of selective early treatment of patent ductus arteriosus with ibuprofen in extreme preterm babies.

Design Within-trial economic evaluation alongside a multicentre, randomized, masked, placebo-controlled trial.

Setting Thirty-two UK tertiary neonatal intensive care units.

Sample Babies born between 23+0 to 28+6 weeks’ gestation, less than 72 hours old and confirmed by echocardiography to have a large PDA.

Methods A cost-effectiveness analysis was conducted from the National Health Service (NHS) and NHS and Personal Social Services perspectives. Nonparametric bootstrapping was used to estimate incremental costs and outcomes which were reported as cost-effectiveness acceptability curves.

Main outcome measures Cost per additional major outcome averted.

Results Ibuprofen is less costly with an average cost per participant of £126,465 compared to £133,260 (-£6,808 (95% CI: £-17,154 to £3,537) for placebo. But it is less effective in terms of major outcomes averted with an absolute effect difference of 0.054 (95% CI: -0.014 to 0.121). The differences in mean cost were mainly attributable to the costs of high dependency care (£2,345, 95% CI -£3,435 to £8,126) and intensive care (£6,718, 95% CI - £12,627 to £26,063) which were higher in the placebo arm. The incremental cost-effectiveness ratio was estimated at £126,846 for an additional case of death, or severe or moderate bronchopulmonary dysplasia avoided by 36 weeks of post-menstrual age.

Conclusions Based on the evidence from this trial, ibuprofen would not be recommended. There is insufficient evidence to suggest that any of the observed detrimental impact on effectiveness would be outweighed by the opportunity cost associated of any saving in costs.

J Bell reports work as Study Statistician on Respiratory & Immunology studies at AstraZeneca via employment at PHASTAR. All other authors state no conflicts of interest.

ISRCTN84264977

The study was funded by the UK NIHR HTA Programme (HTA 11/92/15). The funder was not involved in the identification, design, conduct, and reporting of the analysis.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The UK Medicines and Healthcare Products Regulatory Agency, the NHS Health Research Authority, and the East Midlands Nottingham 2 Research Ethics Committee gave ethical approval for this work.

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Yes

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I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

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Data sharing requests will be considered by the BABY OSCAR management group upon written request. After approval of proposal, or with a signed data access agreement investigator involvement will depend on the discussion and agreement that is reached for the use of the data.