Oral propranolol for prevention of threshold retinopathy of prematurity (ROPROP): protocol of a randomised controlled trial

Abstract

Introduction Retinopathy of prematurity (ROP) is a disease observed in extremely premature infants characterised by visioning-threatening retinal vessel proliferation. Propranolol, a drug used for decades in newborn infants with heart diseases, hypertension and thyrotoxicosis and licenced for infantile haemangiomas, may be effective in halting progression of ROP to severe stages, as suggested by preliminary data from small studies. Methods and analysis ROPROP is an investigator-initiated, multicentre, placebo-controlled double-blind, randomised controlled trial aiming to assess the safety and efficacy of orally administered propranolol to reduce the risk of threshold ROP (stage 3) in extremely preterm infants at 48 weeks postmenstrual age (primary objective) and the rate of infants requiring local interventions for severe ROP (secondary objective). Key inclusion criteria: gestational age <28 weeks, birth weight <1250g, postmenstrual age >= 31 and <37 weeks, incipient ROP (stage 1 or 2, with or without plus disease) and written informed consent by parents or legal guardian. Key exclusion criteria: requirement for open-label propranolol treatment, major congenital malformations (including those with cerebrovascular malformations), known chromosomal anomalies, colobomas and other eye malformations, atrioventricular block grade 2 or 3 and comedication with antiarrhythmics, clonidine, insulin (pharmacodynamic interaction), phenobarbital or rifampicin (pharmacokinetic interaction). The intervention consists of oral propranolol-hydrochloride (1.6 mg/kg/day in three to four divided dosages) or placebo until discharge, for a maximum of 10 weeks. Analysis is by intention to treat. Ethics and dissemination The protocol has received ethical and regulatory approval. Results will be published after peer review irrespective of the study outcome.