Repeated intravenous doses of human umbilical cord-derived mesenchymal stromal cells for bronchopulmonary dysplasia: results of a phase 1 clinical trial with 2-year follow-up.

BACKGROUND: Currently, there is a lack of effective treatments or preventive strategies for bronchopulmonary dysplasia (BPD). Pre-clinical studies with mesenchymal stromal cells (MSCs) have yielded encouraging results. The safety of administering repeated intravenous doses of umbilical cord tissue-derived mesenchymal stromal cells (UC-MSCs) has not yet been tested in extremely-low-gestational-age newborns (ELGANs). AIMS: to test the safety and feasibility of administering three sequential intravenous doses of UC-MSCs every 7 days to ELGANs at risk of developing BPD. METHODS: In this phase 1 clinical trial, we recruited ELGANs (birth weight ≤1250 g and ≤28 weeks in gestational age [GA]) who were on invasive mechanical ventilation (IMV) with FiO2 ≥ 0.3 at postnatal days 7-14. Three doses of 5 × 106/kg of UC-MSCs were intravenously administered at weekly intervals. Adverse effects and prematurity-related morbidities were recorded. RESULTS: From April 2019 to July 2020, 10 patients were recruited with a mean GA of 25.2 ± 0.8 weeks and a mean birth weight of 659.8 ± 153.8 g. All patients received three intravenous UC-MSC doses. The first dose was administered at a mean of 16.6 ± 2.9 postnatal days. All patients were diagnosed with BPD. All patients were discharged from the hospital. No deaths or any serious adverse events related to the infusion of UC-MSCs were observed during administration, hospital stays or at 2-year follow-up. CONCLUSIONS: The administration of repeated intravenous infusion of UC-MSCs in ELGANs at a high risk of developing BPD was feasible and safe in the short- and mid-term follow-up.

Exploring clinical, echocardiographic and molecular biomarkers to predict bronchopulmonary dysplasia.

INTRODUCTION: Bronchopulmonary dysplasia (BPD) is the most common chronic lung disease in childhood, related to prematurity, and the most common cause of pulmonary hypertension (PH) secondary to pulmonary disease in children. Moderate and severe BPD have a worse outcome and relate more frequently with PH. The prediction of moderate or severe BPD development in extremely premature newborns is vital to implement preventive strategies. Starting with the hypothesis that molecular biomarkers were better than clinical and echocardiographic factors, this study aims to explore the ability of clinical, echocardiographic and analytical variables to predict moderate or severe BPD in a cohort of extremely preterm infants. PATIENTS AND METHODS: We designed a prospective longitudinal study, in which we followed a cohort of preterm newborns (gestational age <28 weeks and weight ≤ 1250 grams). In these newborns we recorded weekly clinical and echocardiographic variables as well as blood and tracheal aspirate samples, to analyze molecular biomarkers (IL-6, IL-1, IP10, uric acid, HGF, endothelin-1, VEGF, CCL5). Variables and samples were collected since birth up to week 36 (postmenstrual age), time-point at which the diagnosis of BPD is established. RESULTS: We included 50 patients with a median gestational age of 26 weeks (IQR 25-27) and weight of 871 g (SD 161,0) (range 590-1200g). Three patients were excluded due to an early death. Thirty-five patients (74.5%) developed BPD (mild n = 14, moderate n = 15, severe n = 6). We performed a logistic regression in order to identify risk factors for moderate or severe BPD. We compared two predictive models, one with two variables (mechanical ventilation and inter-ventricular septum flattening), and another-one with an additional molecular biomarker (ET-1). CONCLUSIONS: The combination of clinical and echocardiographic variables is a valuable tool for determining the risk of BPD. We find the two variable model (mechanical ventilation and echocardiographic signs of PH) more practical for clinical and research purposes. Future research on BPD prediction should be oriented to explore the potential role of ET-1.

Sevoflurane for Short Painful Procedures in the Neonatal Intensive Care Unit.

OBJECTIVE: The aim of this study is to evaluate the use and safety of a sedation protocol with sevoflurane for short painful procedures in newborns. STUDY DESIGN: This was a prospective and observational study conducted in a tertiary neonatal intensive care unit. Sevoflurane was recommended in patients undergoing an invasive procedure of short length, especially in those with spontaneous breathing or without venous access. Its safety and efficacy was assessed by continuous monitoring of respiratory and hemodynamic variables and clinical data recording. RESULTS: Sevoflurane was used for 39 procedures, the main indications were: intravitreal bevacizumab injection (12), central venous catheterization (11), and biopsy (6). The median administration length was 14 minutes (range: 5-65 minutes). The median minimum dose was 1.5% (range: 1-3%). The median maximum dose was 2.5% (range: 1-6%). An effective control of nociceptive manifestations was achieved in 35 cases (90%). No major adverse effects were noticed. Main adverse effects were hypotension (8), desaturation (4), and apnea (3). All of them were solved by decreasing (14) or discontinuing (1) the administration of sevoflurane. CONCLUSION: Sevoflurane is relatively easy to use and provides an optimal control of pain-related symptoms. Its prescription should be individualized and more long-term follow-up data are needed.

Off-label mesenchymal stromal cell treatment in two infants with severe bronchopulmonary dysplasia: clinical course and biomarkers profile.

BACKGROUND: Bronchopulmonary dysplasia (BPD) is the most prevalent sequelae of premature birth, for which therapeutic options are currently limited. Mesenchymal stromal cells (MSCs) are a potential therapy for prevention or reversal of BPD. SERIES OF CASES: We report on two infants with severe BPD in whom off-label treatment with repeated intravenous doses of allogeneic bone marrow-derived MSCs were administered. We analyzed the temporal profile of serum and tracheal cytokines and growth factors as well as safety, tolerability and clinical response. The administration of repeated intravenous doses of MSCs in two human babies with severe and advanced BPD was feasible and safe and was associated with a decrease of pro-inflammatory molecules and lung injury biomarkers. Both patients were at very advanced stages of BPD with very severe lung fibrosis and did not survive the disease. CONCLUSIONS: MSCs are a promising therapy for BPD, but they should be administered in early stages of the disease.

The economic impact of prematurity and bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) is one of the most serious chronic lung diseases in infancy and one of the most important sequels of premature birth (prevalence of 15-50%). Our objective was to estimate the cost of BPD of one preterm baby, with no other major prematurity-related complications, during the first 2 years of life in Spain. Data from the Spanish Ministry of Health regarding costs of diagnosis-related group of preterm birth, hospital admissions and visits, palivizumab administration, and oxygen therapy in the year 2013 were analyzed. In 2013, 2628 preterm babies were born with a weight under 1500 g; 50.9% were males. The need for respiratory support was 2.5% needed only oxygen therapy, 39.5% required conventional mechanical ventilation, and 14.9% required high-frequency ventilation. The incidence of BPD was of 34.9%. The cost of the first 2 years of life of a preterm baby with BPD and no other major prematurity-related complications ranged between 45,049.81 € and 118,760.43 €, in Spain, depending on birth weight and gestational age. If the baby required home oxygen therapy or developed pulmonary hypertension, this cost could add up to 181,742.43 €. CONCLUSION: Prematurity and BPD have an elevated cost, even for public health care systems. This cost will probably increase in the coming years if the incidence and survival of preterm babies keeps rising. The development of new therapies and preventive strategies to decrease the incidence of BPD and other morbidities associated with prematurity should be a priority. What is known: • Bronchopulmonary dysplasia (BPD) is a serious chronic lung disease related with premature birth. • BPD is an increasing disease due to the up-rise in the number of premature births. What is new: • The economic cost of preterm birth and BPD has never before been estimated in Spain nor published with European data. • Preterm babies with BPD and a good clinical outcome carry also an important economic and social burden.

Pulmonary vein stenosis of ex-premature infants with pulmonary hypertension and bronchopulmonary dysplasia, epidemiology, and survival from a multicenter cohort.

BACKGROUND: Pulmonary vein stenosis is emerging as an important clinical problem in ex-premature infants. METHODS: We sought to describe the epidemiology of pulmonary vein stenosis affecting ex-premature infants by a multicenter retrospective cohort study of patients from seven children's hospitals diagnosed between 2000-2014. RESULTS: We identified 39 ex-premature patients (26 males, median gestational age 28 weeks range 22-36 weeks, birth weight 1.1 kg range 433-2645-g) with pulmonary vein stenosis. Median age at diagnosis was 6.5 months (1 month-6 years). Presentation with pulmonary hypertension occurred in 26/39 (67%) and 29/39 (74%) had bronchopulmonary dysplasia, 15 (39%) were born of twin pregnancies with unaffected twin siblings. A median of 5 (range 1-25) echocardiograms was performed prior to diagnosis. The diagnosis was made using echocardiography in 22/39 (56%), by multi-detector contrast computed tomography scan (CT) in 8/39 (21%), cardiac catheterization in 6/39 (15%) patients, magnetic resonance imaging in 3/39 (8%). Freedom from death or re-stenosis was 73% at 1-year, 55% at 2, 5, and 10 years. Factors associated with shorter survival or re-stenosis were stenosis of ≥3 pulmonary veins (P < 0.01), bilateral pulmonary vein stenosis (P < 0.01) small for gestational age (P = 0.05), aged <6 months at diagnosis (P < 0.01). CONCLUSION: Pulmonary vein stenosis of ex-premature infants is a complex problem with poor survival, delayed diagnosis, and unsatisfactory treatment. The lack of concordance in twins suggests epigenetic or environmental factors may play a role in the development of pulmonary vein stenosis. In ex-premature infants with pulmonary hypertension and bronchopulmonary dysplasia a focused echocardiographic assessment of the pulmonary veins is required with further imaging if the echocardiogram is inconclusive.

Phase 1 study of two inodilators in neonates undergoing cardiovascular surgery.

BACKGROUND: Inodilators are routinely used in cardiovascular surgery with cardiopulmonary bypass (CPB). Information regarding safety and tolerability of the novel molecule, levosimendan (LEVO), in newborns is anecdotal; no pharmacokinetic data in this population are available. METHODS: This was a phase I, randomized, and blinded study. Neonates undergoing surgical repair for congenital heart defects received stepwise dose increases of milrinone (MR; 0.5-1 µg/kg/min, n = 9) or LEVO (0.1-0.2 µg/kg/min, n = 11) as an i.v. continuous infusion, starting before CPB. Infants had continuous, time-locked, physiological, and near-infrared spectroscopy (NIRS) (cerebral and peripheral) recordings during the first 24 h, and at 48 and 96 h postsurgery. Serial biochemistry and pharmacokinetic studies were performed. RESULTS: During the first 24 h postsurgery, patients showed time-related, group-independent increased cerebral tissue oxygenation and decreased diastolic blood pressure; in addition, group-dependent differences in heart rate and peripheral perfusion were found. Early postsurgery, MR-treated infants showed lower pH, higher glycemia, and higher inotrope score. The groups differed in cerebral NIRS-derived variables from 24 to 96 h. Study drug withdrawal at 96 h was more frequent with LEVO. LEVO intermediate metabolites were detected in plasma at day 14 after surgery. CONCLUSION: LEVO is well tolerated in critically ill neonates. LEVO may have advantages over MR in terms of the dosing regimen.