ESPE Abstracts

Introduction: Hypochondroplasia is a rare genetic growth-related condition primarily caused by FGFR3 variants that lead to decreased endochondral bone growth, disproportionate short stature and other medical complications. It shares pathogenetic and phenotypic similarities to achondroplasia. Outside of Japan, there are no approved pharmacological treatments for hypochondroplasia. Vosoritide, a C-type natriuretic peptide analog, is an approved first-in...

Objectives: No validated achondroplasia (ACH)-specific patient reported outcome (PRO) or clinician-reported outcome (ClinRO) measures are available. A detailed review of generic PRO and ClinRO measures was performed to select relevant tools for further evaluation in a qualitative study.Methods: Published literature describing medical challenges and impacts among children with ACH was reviewed to identify important concep...

Objectives: Individuals with achondroplasia (ACH) experience medical, emotional and functional detriments during their lifetime. A comprehensive research initiative was conducted to include combined concept elicitation (CE) and cognitive debriefing (CD) interviews and mapping of concepts to identify the most relevant available patient-reported outcome (PRO) measures for inclusion in studies of ACH.Methods: Combined CE/CD...

Background and Objectives: Achondroplasia (ACH) is characterized by severe short stature with a height deficit of approximately 6 SDS below that of average stature. Our objective was to evaluate the impact of height deficit on health-related quality of life (HRQoL) and functional independence in children with ACH.Methods: Height Z-score, HRQoL, and functional independence data were obtained from children with ACH who enr...

Achondroplasia (ACH) is the most common form of dwarfism, occurring in 1: 20,000 births. ACH is caused by gain-of-function mutations in the fibroblast growth factor receptor 3 (FGFR3) gene that interfere with endochondral ossification. Clinically significant morbidities are frequent in ACH; however, there are currently no approved therapies that target the underlying pathobiology. C-type natriuretic peptide (CNP) is an attractive target as it has the potential to inhi...

Objectives: Achondroplasia (ACH), caused by a mutation in the fibroblast growth factor receptor 3 gene (FGFR3), leads to inhibition of endochondral bone growth. Vosoritide is a biological analogue of C-type natriuretic peptide (CNP), a potent stimulator of endochondral bone growth. A Phase 2, open-label, sequential cohort, dose-escalation study was conducted to evaluate the safety, tolerability, and efficacy of vosoritide for 24 months in children with ACH aged 5&#150...

Background: Bone age (BA) is commonly used in pediatrics to define skeletal maturity for medical and non-medical purposes. Normal range is represented by 2 standard deviations (SDs) above and below the mean. A BA greater than ±2 SDs from the chronological age (CA) is considered abnormal. BA in achondroplasia (ACH) has not been fully characterized; calculation is challenging given difficulties in comparing x-rays with standard radiographs if using the Greuli...

Background: ACH, the most common short-limbed skeletal dysplasia, is characterized by defective endochondral ossification resulting from gain-of-function mutations in the fibroblast growth factor receptor 3 (FGFR3) gene, a negative regulator of endochondral bone formation. Current treatment options are non-targeted, ineffective, or painful interventions aimed at preventing or treating complications. Infigratinib is an orally bioavailable and selective...

Background: ACH is the most common short-limbed skeletal dysplasia, affecting between 1 in 15,000 to 1 in 30,000 live births. Children and adults with ACH have disproportionate short stature, with a final height of approx. 131 cm for males and 124 cm for females. People with ACH are prone to significant co-morbidities, including obstructive sleep apnea, chronic otitis media with conductive hearing loss, spinal stenosis, and a propensity towards obesity. In som...

Introduction: Vosoritide increases growth in children with achondroplasia aged 5–18 years (Savarirayan et al, Genet Med, 2021). We recently reported results from a phase 2, randomized, double-blind, placebo-controlled study (111-206) in young children with achondroplasia aged 3 months–5 years Here we present results from an open-label extension study (111-208) spanning up to 4 years of treatment in the children aged 2-5 years at study star...