MICA: Optimising brain protection and reducing birth asphyxia disability: safety and efficacy of early high dose MELATONIN and COOLING with late EPO

Problems around the time of birth causing a lack of oxygen to the baby can cause disordered brain function called neonatal encephalopathy (NE), which can result in long term brain damage and cerebral palsy. Cooling a baby by 3 degrees Celsius for three days as soon as possible after birth has been shown to be safe and leads to long term brain protection and improved outcome even to school age. The number of babies that need to be treated with cooling to prevent one from being dead or disabled is 6-7. Cooling has been endorsed by the National Institute for Clinical Excellence (NICE) and adopted in neonatal intensive care units around the UK for babies with moderate to severe NE. However, although cooling is a major step forward for babies with NE, 44-53% of babies still have adverse outcomes.

Over the last 5 years, studies have been performed in the laboratory of N Robertson (PI) and S Juul (co-applicant) on 1. melatonin and 2. erythropoietin (Epo) respectively; these studies have both shown that adding one of these agents to cooling is safe and leads to better outcomes in animals (melatonin) and in animals and babies (Epo). These agents act at different parts of the cascade of injury after hypoxia:

1. Melatonin is a naturally occurring hormone produced by the pineal gland which entrains the day/night cycle at physiological levels. At higher levels (plasma levels 10,000 times higher than normal night time levels), melatonin has powerful non-receptor actions to scavenge damaging free radicals. Our studies have shown the critical importance of reaching the therapeutic range of melatonin as quickly as possible after the injury for most benefit. Our collaboration with the pharmaceutical company, Chiesi, started in 2013 following our initial study showing significant augmentation of brain protection with melatonin at 10 mins after hypoxia. Chiesi has developed a novel melatonin formulation which is safe for babies; this new formulation was assessed recently in our laboratory and the optimal rate and dosing of melatonin to achieve therapeutic levels at 3h rather than 8h has been calculated.

2. Epo is a protein originally identified for its role in stimulating red blood cell generation. Epo has brain protection and repair and regeneration properties and have been shown to be protective when starting in the subacute phase up to 1 week after the injury in animals and at 16.5 h in babies with cooling.S Juul has been a leader in the Epo brain protection field and has unique knowledge of dose response and safety and is PI on the 2 clinical trials of Epo brain protection in the USA.

Our aim is to perform a study which addresses the following questions:
1. Does the combination of an optimised high dose melatonin given early on at 1h after the injury and at a faster infusion rate and late Epo at 24h after rewarming lead to better brain protection than cooling alone (triple versus single therapy)

2. Does triple therapy (Cooling, melatonin and Epo) lead to bettie protection than double therapy (Cooling play melatonin or cooling plus Epo)

3. Does the optimised high dose melatonin with therapeutic levels achieved in 3h after injury lead to improved protection compared to our previous protocol where therapeutic levels were achieved at 8h after injury.

We will use an established piglet intensive care model of NE to address these questions. Intensive care and monitoring can be given to the piglet, the size allows for the same intravenous lines and catheters to be used as in babies, the medications are all based on protocols from the NICU and the maturational stage of the piglet brain is similar to human brain with the brain growth spurt occurring around birth. We use the same 3 Tesla MRI system and same sequences as we do in babies with NE, making the data clinically relevant and translational.

These data, if positive, will be translated to clinical trials in babies and could lead to significant benefit to outcomes.

Intrapartum-related events are the 4th leading cause of childhood mortality worldwide and lead to almost 1 million neurodisabled survivors. Infants exposed to a perinatal insult typically present with neonatal encephalopathy (NE). In high income countries, therapeutic hypothermia is a safe and effective therapy reducing adverse outcome by 15%. However, 44-53% of babies still have adverse outcomes; adjunct therapies are needed.

Pre-clinical studies have shown that early high dose melatonin can augment hypothermic brain protection; melatonin is likely to be most effective early on after hypoxia by its diverse anti-oxidative mechanisms preventing free radical induced damage. In collaboration with our project partner Chiesi, a novel melatonin formulation has been developed and optimised pharmacokinetics modelled. Both pre-clinical and clinical studies show Epo augments hypothermic brain protection; Epo has beneficial effects in the subacute phase, promoting brain repair and neurogenesis.

This is a randomised, placebo controlled pre-clinical safety and efficacy trial (group I pilot PK, 4 randomised groups II-V). We will use the Large White newborn piglet model (age <24h) to assess effects of early melatonin with cooling and late Epo after rewarming on brain protection.

Using a clinically relevant primary outcome measure - MRS Lac/NAA in white and grey matter AND immunohistochemistry (TUNEL) we hypothesise:
1. Triple therapy with early MELATONIN (18mg/kg over 2h administered at 1, 24, 48h with Cmax at 3h) with cooling 33.5oC (1-13h) and subacute Epo after rewarming (1000U/kg at 36,48,60,72h) will improve primary outcome measures compared to single therapy (cooling alone) and double therapy (cooling and melatonin or cooling and Epo)
2. Optimising the melatonin dose, timing and infusion rate to obtain Cmax at 3h (instead of 8h in a previous study) improves brain protection

Positive results from this study will guide the rapid translation to clinical trials

This study will advance scientific knowledge on the likely additive protection of three therapies targeted at different aspects of the brain injury cascade at different times.The study will provide proof of concept of the possibility of augmentation of protection with triple therapy - already it is known that melatonin and Epo when individually combined with cooling augment protection.

Health and wellbeing of babies with neonatal encephalopathy will improve. If the triple therapy is beneficial, the number of infants needed to be treated to save one from adverse outcome will reduce.

Local and national economies will benefit from increased disability-free lives. Litigation costs will reduce; UK obstetric claims are £500 million/year. Costs of education and care for children with neurodisabilities will fall. Based on current lifetime costs for each child with cerebral palsy (£750,000) and economic benefit per additional healthy life (£800,000), reducing the incidence of cerebral palsy by 10% will save the UK economy £30 million per year.

Healthcare professional and research scientists across neuroscience and paediatrics will benefit from the concepts arising from this study that can be applied in stroke and paediatric brain injury.

The pre-clinical study will inform regulatory bodies and clinical neonatologists on the safety and PK of melatonin and Epo and will reduce the need for phase I studies in babies (this has been discussed with the MHRA previously).