Long-term inhaled iloprost use in children with pulmonary arterial hypertension

Effects of oral sildenafil on exercise capacity in children with pulmonary arterial hypertension: a randomised trial

Objective

The 16-week, randomised, double-blind Sildenafil in Treatment-Naïve Children, Aged1-17 years, with Pulmonary Arterial Hypertension (STARTS-1) study assessed the effect of sildenafil on cardiopulmonary exercise testing (CPET) in treatment-naïve paediatric patients with pulmonary arterial hypertension (PAH) and included a long-term extension (STARTS-2). CPET has rarely been performed in paediatric patients and we assessed both aerobic capacity with peak oxygen consumption (PVO₂) and ventilatory inefficiency with the slope of ventilation to carbon dioxide production (VE/VCO₂ slope).

Methods

Patients (aged 1-17 year) were randomised to low (10 mg), medium (10-40 mg) and high (20-80 mg) sildenafil dose groups. Patients previously treated with placebo in STARTS-1 were randomised to one of three blinded sildenafil dose groups for STARTS-2. CPET was assessed by cycle ergometry at baseline, week 16, and year 1.

Results

Of the 234 children randomised, 115 could exercise. At week 16, the combined sildenafil dose group had a 7.7% increase in mean PVO₂ percent change from baseline compared with placebo (95% CI -0.2% to 15.6%; p=0.056); at year 1, a significant increase in mean percent change in PVO₂ from baseline was only observed in the low-dose group (mean of 12.4% and 95% CI 3% to 21.8%). For VE/VCO₂ slope, at week 16, the combined dose group had a -9.7% mean change from baseline compared with placebo (95% CI -14.9% to -4.5%; p<0.001); at year 1, there were no significant changes for any dose group.

Conclusions

Sildenafil monotherapy (combined sildenafil dose group) appeared to improve short-term VE/VCO₂ slope versus placebo but did not significantly improve PVO₂ in treatment-naïve paediatric patients with PAH who were developmentally able to exercise.

Trial registration number

NCT00159913 for A1481131, NCT00159874 for A1481156.

The Efficacy and Safety of Aerosolized Iloprost in Pulmonary Arterial Hypertension: A Systematic Review and Meta-Analysis

BACKGROUND

This systematic review and meta-analysis was conducted to investigate the efficacy and safety of the chronic administration of aerosolized iloprost for pulmonary arterial hypertension (PAH).

METHODS

All the relevant studies were obtained from three databases, namely, PubMed, Web of Science and the Cochrane Library, from the inception of each database to June 1, 2018. In our study, chronic treatment was defined as a period lasting at least 3 months. The rate of each event was analyzed by SPSS as a percentage with 95% confidence intervals (CIs). For the meta-analysis, a randomized effect model or a fixed effect model was applied according to the results of the heterogeneity test.

RESULTS

Ten studies were included in this study, with a total of 370 patients treated with inhaled iloprost, including 214 in five randomized controlled trials and 156 in five prospective clinical trials. Among the patients who received inhaled iloprost, there was a significant improvement in the 6-min walk distance (6MWD) in the short-medium and prolonged treatment groups. Notably, the functionality improved by at least 1 class in 48.7% of the treated patients. In all the pooled studies, the estimated 3-month, 6-month, 1-year and 2-year event-free survival rates were 96.6%, 92.3%, 62.6% and 39.6%, respectively. In addition, there were eight adverse drug responses.

CONCLUSION

In this systematic review and meta-analysis, inhaled iloprost has been shown to be a safe and well-tolerated agent for PAH in the first 3 months after diagnosis. If used for a prolonged period, aerosol iloprost monotherapy could contribute to an unsatisfactory improvement in vascular remodeling and even a decreased event-free survival rate.

Diagnosis and treatment of pediatric pulmonary arterial hypertension

INTRODUCTION

Pediatric pulmonary arterial hypertension (PAH) remains a rare and severe disease with a poor prognosis. PAH may be idiopathic, heritable or associated with systemic conditions in particular associated with congenital heart disease. Areas covered: A thorough and extensive diagnostic approach is required for a correct diagnosis. The outcome has improved over the last decade with a better diagnostic approach and with the initiation of new targeted therapies. However, there is still significant progress to achieve as there is still no cure for this devastating disease. Expert opinion: Adapted clinical studies to define the best therapeutic approach are needed. Even if the treatment approach is still mainly derived from adult data and expert consensus, several studies and registries are currently underway and should deliver important information in the next future. This review aims to give an overview of the current diagnosis and treatment strategies of PAH.

Current and advancing treatments for pulmonary arterial hypertension in childhood

Pulmonary arterial hypertension (PAH) is a severe and progressive intrinsic disease of the precapillary lung vasculature. Since the introduction of PAH-targeted drugs, survival of PAH patients seems to have improved. Randomized controlled trials have led to evidence-based guidelines to direct treatment in adults. However, since disease characteristics differ between adults and children, it is hazardous to simply extrapolate these guidelines to children. Moreover, pediatric data on treatment strategies and how to assess treatment response remain virtually absent. Optimal treatment strategies are highly needed to guide therapy and improve survival in children with PAH. This review provides an overview of currently available treatments for PAH and the limited efficacy and safety data in children (with the exclusion of perinatal pulmonary vascular diseases, as persistent pulmonary hypertension of the newborn). We also discuss potential treatment goals and how the available data can be translated into treatment strategies in pediatric PAH.