Oral melatonin as a new tool for neuroprotection in preterm newborns: study protocol for a randomized controlled trial

Abstract

Background: Prevention of neurodevelopmental impairment due to preterm birth is a major health challenge. Despite advanced obstetric and neonatal care, to date there are few neuroprotective molecules available. Melatonin has been shown to have anti-oxidant/anti-inflammatory effects and to reduce brain damage, mainly after hypoxic ischemic encephalopathy. The planned study will be the first aiming to evaluate the capacity of melatonin to mitigate brain impairment due to premature birth.

Method: In our planned prospective, multicenter, double-blind, randomized vs placebo study, we will recruit, within 96 h of birth, 60 preterm newborns with a gestational age ≤ 29 weeks + 6 days; these infants will be randomly allocated to oral melatonin, 3 mg/kg/day, or placebo for 15 days. After the administration period, we will measure plasma levels of malondialdehyde, a lipid peroxidation product considered an early biological marker of melatonin treatment efficacy (primary outcome). At term-equivalent age, we will evaluate neurological status (through cerebral ultrasound, cerebral magnetic resonance imaging, vision and hearing evaluations, clinical neurological assessment, and screening for retinopathy of prematurity) as well as the incidence of bronchodysplasia and sepsis. We will also monitor neurodevelopmental outcome during the first 24 months of corrected age (using the modified Fagan Test of Infant Intelligence at 4-6 months and standardized neurological and developmental assessments at 24 months).

Discussion: Preterm birth survivors often present long-term neurodevelopmental sequelae, such as motor, learning, social-behavioral, and communication problems. We aim to assess the role of melatonin as a neuroprotectant during the first weeks of extrauterine life, when preterm infants are unable to produce it spontaneously. This approach is based on the supposition that its anti-oxidant mechanism could be useful in preventing neurodevelopmental impairment. Considering the short- and long-term morbidities related to preterm birth, and the financial and social costs of the care of preterm infants, both at birth and over time, we suggest that melatonin administration could lead to considerable saving of resources. This would be the first study addressing the role of melatonin in very low birth weight preterm newborns, and it could provide a basis for further studies on melatonin as a neuroprotection strategy in this vulnerable population.

Trial registration: ClinicalTrials.gov NCT04235673 . Prospectively registered on 22 January 2020.

Keywords: Anti-oxidant; Infants; Malondialdehyde; Melatonin; Neuro-cognitive development; Neuroprotection; Preterm newborn.