Efficacy of Once-weekly Somatrogon in Children with Growth Hormone Deficiency After Switching from Daily Therapy

INTRODUCTION: Long-acting Growth Hormone (LAGH) analogs represent a promising alternative to daily growth hormone (GH) therapy, aiming to improve adherence without compromising efficacy. Among them, somatrogon is the only LAGH currently available in Italy for pediatric use. OBJECTIVE: The objective of this study is to evaluate growth outcomes and IGF-1 variability along with adherence in pediatric patients with growth hormone deficiency (GHD) after switching from daily GH to weekly somatrogon. METHODS: This retrospective, monocentric study involved 23 children and adolescents affected by GHD and in treatment with somatrogon for at least 12 months, after switching from daily therapy. We analyzed changes in growth velocity, serum IGF-1 and height velocity compared to target age-based references before and after the switch. To account for the age-related variability in our cohort, IGF-1 levels were then expressed as Standard Deviation Score (IGF-1 SDS), to quantify how much an individual value deviates from the age and sex-matched population mean. A questionnaire was administered to evaluate adherence and patients' preferences. RESULTS: Mean height velocity was slightly higher after the therapeutic switch (7.91 ± 1.7 cm/year vs. 7.12 ± 1.3 cm/year, p = 0.04), but no significant differences were observed when growth velocity was normalized to age-based targets or when comparing IGF-1 and IGF-1 SDS levels. Patients preferred the weekly therapy, even if missing doses and a few side effects were still reported. DISCUSSION: Our findings suggest that somatrogon treatment is as effective as daily GH treatment in terms of growth velocity and IGF-1 levels in a pediatric population with growth hormone deficiency. Weekly therapy also seemed to be more manageable for the patients and their families. CONCLUSION: Weekly somatrogon maintains growth-promoting effects comparable to daily GH therapy in pediatric patients with GHD. Patients' adherence and satisfaction contribute to making this therapy a valid alternative to daily treatments.