Randomised Phase 2b trial of rhIGF-1/rhIGFBP-3 (OHB-607) for bronchopulmonary dysplasia prevention in preterm neonates: study protocol

introductionBronchopulmonary dysplasia (BPD) is the most common complication of prematurity, characterised by impaired alveolarisation and pulmonary vascular development. BPD has been associated with an increased risk of respiratory morbidity, neurodevelopmental impairment and death, intensifying a lifelong health and economic burden. The current standard of neonatal care is primarily supportive, with no approved therapies to restore lung development, promote maturation and lung growth or prevent long-term sequelae. Therefore, there is a critical unmet need for novel interventions, particularly in high-risk, extremely premature (EP) infants. In EP infants, serum insulin-like growth factor-1 (IGF-1) levels decrease rapidly and remain low for the first weeks after birth relative to the corresponding foetal levels in utero. METHODS AND ANALYSIS: OHB-607, a recombinant human IGF-1 combined with its binding protein-3, may replenish IGF-1 during this period of deficiency and support lung and vascular maturation. OHB-607 is being investigated as a first-line therapy to prevent severe BPD in EP infants in a Phase 2b, multicentre, open-label, randomised trial. Here, we present the Phase 2b study protocol. Target enrolment is 338 EP infants. To mimic physiological IGF-1 levels in utero, OHB-607 will be administered starting within 24 hours of birth until 29 ETHICS AND DISSEMINATION: Findings will be disseminated via local and international congresses and publications. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (NCT03253263), Clinicaltrialsregister.eu (EudraCT: 2018-001393-16), Euclinicaltrials.eu (EUCT: 2024-515914-41-00) and Pmda.go.jp (PMDA: jRCT2031240339).