A Compartment-Based Mathematical Model for Studying Convective Aerosol Transport in Newborns Receiving Nebulized Drugs during Noninvasive Respiratory Support

A Randomized, Controlled Trial to Investigate the Efficacy of Nebulized Poractant Alfa in Premature Babies with Respiratory Distress Syndrome

OBJECTIVE

To investigate the efficacy and safety of nebulized poractant alfa (at 200 and 400 mg/kg doses) delivered in combination with nasal continuous positive airway pressure compared with nasal continuous positive airway pressure alone in premature infants with diagnosed respiratory distress syndrome.

STUDY DESIGN

This randomized, controlled, multinational study was conducted in infants at 28^0/7 to 32^6/7 weeks of gestation. The primary outcome was the incidence of respiratory failure in the first 72 hours of life, defined as needing endotracheal surfactant and/or mechanical ventilation owing to prespecified criteria. Secondary outcomes included the time to respiratory failure in the first 72 hours, duration of ventilation, mortality, incidence of bronchopulmonary dysplasia, and major associated neonatal comorbidities. In addition, the safety and tolerability of the treatments were assessed reporting the number and percentage of infants with treatment-emergent adverse events and adverse drug reactions during nebulization.

RESULTS

In total, 129 infants were randomized. No significant differences were observed for the primary outcome: 24 (57%), 20 (49%), and 25 (58%) infants received endotracheal surfactant and/or mechanical ventilation within 72 hours in the poractant alfa 200 mg/kg, poractant alfa 400 mg/kg, and nasal continuous positive airway pressure groups, respectively. Similarly, secondary respiratory outcomes did not differ among groups. Enrollment was halted early owing to a change in the benefit-risk balance of the intervention. Nebulized poractant alfa was well-tolerated and safe, and no serious adverse events were related to the study treatment.

CONCLUSIONS

The intervention did not decrease the likelihood of respiratory failure within the first 72 hours of life.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03235986.

Aerosol drug delivery to spontaneously-breathing preterm neonates: lessons learned

Delivery of medications to preterm neonates receiving non-invasive ventilation (NIV) represents one of the most challenging scenarios for aerosol medicine. This challenge is highlighted by the undersized anatomy and the complex (patho)physiological characteristics of the lungs in such infants. Key physiological restraints include low lung volumes, low compliance, and irregular respiratory rates, which significantly reduce lung deposition. Such factors are inherent to premature birth and thus can be regarded to as the intrinsic factors that affect lung deposition. However, there are a number of extrinsic factors that also impact lung deposition: such factors include the choice of aerosol generator and its configuration within the ventilation circuit, the drug formulation, the aerosol particle size distribution, the choice of NIV type, and the patient interface between the delivery system and the patient. Together, these extrinsic factors provide an opportunity to optimize the lung deposition of therapeutic aerosols and, ultimately, the efficacy of the therapy.In this review, we first provide a comprehensive characterization of both the intrinsic and extrinsic factors affecting lung deposition in premature infants, followed by a revision of the clinical attempts to deliver therapeutic aerosols to premature neonates during NIV, which are almost exclusively related to the non-invasive delivery of surfactant aerosols. In this review, we provide clues to the interpretation of existing experimental and clinical data on neonatal aerosol delivery and we also describe a frame of measurable variables and available tools, including in vitro and in vivo models, that should be considered when developing a drug for inhalation in this important but under-served patient population.