Our overall objective is to conduct a safety study with inhaled ciclesonide to evaluate known glucocorticoids (sGC)-related acute and intermediate toxic effects while measuring for the first time in neonates its systemic absorption and potential bioactivity (i.e. activation of primary target, the GR, in blood cells).

Preterm infants born before 30 weeks gestation are at increased risk of developing bronchopulmonary dysplasia (BPD), a leading cause of death and long-term pulmonary insufficiency. Both hydrocortisone and synthetic glucocorticoids (sGC) are commonly used to prevent BPD in premature infants. Clinical trials have shown that hydrocortisone targeted to infants with emerging lung disease does not prevent BPD, while inhaled sGC therapy has shown mixed efficacy in clinical trials. Dexamethasone (DEX) has been shown in clinical trials to reduce BPD rates in premature infants but is associated with short term and long-term adverse effects including cerebral palsy. There is an unmet need for efficacious Glucocorticoid (GC) therapy in premature infants to prevent BPD without encumbering serious adverse events. To address this challenge, our group has been investigating ciclesonide (CIC), a sGC pro-drug that in the inhaled form is FDA approved for use in asthma and allergic rhinitis in older children. Our published and ongoing work has shown that DEX and CIC regulate GR transcriptional targets and several genes implicated in lung protective effects in neonatal rats. Remarkably, CIC does not suppress somatic growth nor IGF-1 levels, induce hyperglycemia, or cause neuroanatomical changes in the cerebral cortex of neonatal rats, which are known pathologies caused by DEX in premature infants. Furthermore, ongoing studies reveal that CIC is as efficacious as DEX in preventing lung injury in a hyperoxia-model of experimental BPD. This study tests the hypothesis that CIC will have minimal systemic absorption and a favorable safety profile in premature infants at risk of developing BPD.

The fear of long-term neurological adverse effects has limited optimal use of sGC therapy to prevent BPD. This application is significant as it proposes to repurpose CIC, an existing sGC, for novel therapeutic use in preterm infants to prevent BPD. CIC is already FDA-approved for use in children >5 years for allergic rhinitis and asthma, and can be used on a compassionate basis down to 2 years of age. The investigators believe our study is impactful and translationally relevant as it addresses an unmet need for efficacious GC therapy to prevent BPD in premature infants without encumbering the neurological and somatic adverse effects. Successful testing of our hypothesis will pave the way for a large, multicenter randomized control trial of CIC therapy in premature infants to prevent BPD.

Inclusion Criteria:

• Viable Infants born between 23 0/7 - 29 6/7 gestation
• Requiring invasive (through an endotracheal tube) mechanical ventilation
• Between day of life 8 to 35.
• Infants have not received dexamethasone for 120 hours
• If receiving hydrocortisone, then receiving ≤ 1mg/kg/day

Exclusion Criteria:

• Infants with major congenital lung or other organ anomalies, life-threatening illness, active sepsis or NEC, and grade IV hemorrhage will be excluded.
• Infants receiving DEX therapy will be excluded.
• We will exclude infants who have had ≥ 1 glucose level > 150mg in the 24 hours prior to study entry or those on insulin therapy to treat hyperglycemia. We will exclude infants who have hypertension (>95% centile for gestational age) in the 48 hours prior to study entry.
• For small for gestational age, we will exclude infants with a birthweight < 5% centile for gestational age.
• Infants with history of recent pulmonary hemorrhage (within 72 hours of study entry) will also be excluded.
• Infants receiving or have received any dexamethasone in the prior 120 hours.
• Infants receiving >1mg/kg/day of hydrocortisone.
• Infants receiving any other inhaled or systemic steroid.