Near-adult height outcomes in patients treated with rhIGF-1 for severe growth failure: real-world IGFD Registry data.

Abstract

Context: The Global Increlex® Growth Forum Database (IGFD) Registry monitors real-world effectiveness and safety of recombinant human insulin-like growth factor (rhIGF-1; Increlex® [mecasermin]) treatment in children and adolescents with severe growth failure due to severe primary insulin-like growth factor-I deficiency (SPIGFD).

Objective: To report characteristics, effectiveness, and safety data from patients receiving rhIGF-1 treatment who achieved near-adult height (NAH), and determine factors that predict height gain to NAH.

Methods: Descriptive analyses of patients included in the Global IGFD Registry (NCT00903110) who achieved NAH are reported for the overall population, treatment-naïve prepubertal (NPP) patients, and patients with Laron syndrome. Linear regression analyses of height gain to NAH are also reported.

Results: 102 patients enrolled in the Global IGFD Registry achieved NAH at data cut-off (April 20, 2023). Mean age at rhIGF-1 treatment initiation was 11.8 years; median treatment duration was 3.9 years. Mean (SD) height standard deviation score (HtSDS) gain from rhIGF-1 initiation to NAH was 0.9(1.1). In NPP patients, mean (SD) HtSDS gain was 1.4(1.0). Almost half of NPP patients reached NAH within the normal range. Despite improved height in patients with Laron syndrome, only 10.5% reached NAH within the normal range; three patients with Laron syndrome were NPP. Treatment naivety was predictive of height gain in the overall NAH population. Safety data aligned with previous reports.

Conclusions: In a real-world setting, despite patients with SPIGFD initiating rhIGF-1 treatment at a relatively advanced age, rhIGF-1 treatment resulted in improved NAH. Greatest improvements in height outcomes were observed in NPP patients.