Near-Adult Height Outcomes in Patients Treated With rhIGF-1 for Severe Growth Failure: Real-World IGFD Registry Data

Area of Science:

• Pediatric Endocrinology
• Growth Hormone Therapy
• Rare Genetic Disorders

Background:

• The Global Increlex® Growth Forum Database (IGFD) Registry tracks the real-world effectiveness and safety of recombinant human insulin-like growth factor-1 (rhIGF-1; Increlex® [mecasermin]) in children and adolescents with severe growth failure due to severe primary insulin-like growth factor-I deficiency (SPIGFD).
• Monitoring treatment outcomes is crucial for optimizing therapeutic strategies in this patient population.

Purpose of the Study:

• To analyze the characteristics, effectiveness, and safety of rhIGF-1 treatment in patients who achieved near-adult height (NAH).
• To identify predictive factors for height gain leading to NAH.
• To evaluate outcomes in specific subgroups, including treatment-naïve prepubertal (NPP) patients and those with Laron syndrome.

Main Methods:

• Descriptive analyses of 102 patients from the Global IGFD Registry who achieved NAH.
• Subgroup analyses were performed for NPP patients and patients with Laron syndrome.
• Linear regression models were used to determine factors predicting height gain to NAH.

Main Results:

• The mean height standard deviation score (HtSDS) gain from rhIGF-1 initiation to NAH was 0.9(1.1) across the overall population.
• NPP patients achieved a greater mean HtSDS gain of 1.4(1.0), with nearly half reaching normal height range at NAH.
• Treatment naivety was a significant predictor of height gain; safety data were consistent with previous reports.

Conclusions:

• rhIGF-1 treatment effectively improved NAH in patients with SPIGFD in a real-world setting, even when initiated at a later age.
• NPP patients experienced the most substantial improvements in height outcomes.
• The findings support the use of rhIGF-1 for managing severe growth failure in SPIGFD, particularly in younger, treatment-naïve individuals.