Peer-reviewed article
Extension of the Phase 3 Trial of Somatrogon in Children with Growth Hormone Deficiency: 3 Years of Safety and Efficacy.
Stawerska R, Choe J, Wang R, Wajnrajch MP, Cara JF et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study tested somatrogon, a once-weekly growth hormone injection, in children with growth hormone deficiency over 3 years. Children who received somatrogon showed sustained improvements in growth velocity and height, with most side effects being mild. The treatment was well tolerated with no new safety concerns identified over the extended follow-up period.
Key points
- Mean height velocity was sustained at 8.11 cm/year in year 1 and 7.91 cm/year in year 2 of extended treatment
- Height SD score improved from -1.42 to -0.95 over the 2-year extension period
- Most adverse events were mild to moderate; injection site pain and redness were the most common treatment-related side effects
- Children who switched from daily somatropin to weekly somatrogon showed similar growth improvements as those on somatrogon continuously
- About one quarter of patients required dose reductions due to elevated IGF-I levels at consecutive assessments
Limitations
The study does not include a control group comparison for the extension phase, as it was open-label. The document does not provide information about long-term outcomes beyond 3 years or comparisons with untreated children.
Abstract
Introduction Somatrogon is a once-weekly, long-acting growth hormone approved to treat children with growth hormone deficiency (GHD). This study evaluated the long-term efficacy and safety of once-weekly somatrogon in children with GHD following up to 3 years of treatment. Methods During the 12-month main study, patients were randomized 1:1 to once-weekly somatrogon (0.66 mg/kg/week) or once-daily somatropin (0.24 mg/kg/week). Patients could then enter an open-label extension (OLE), wherein somatrogon-treated patients continued receiving somatrogon and somatropin-treated patients switched to somatrogon (0.66 mg/kg/week). Data to the end of the second year of the OLE (OLE year [Y] 2) are reported. Of the 222 patients who completed the main study, 212 entered OLE Y1 and 177 entered OLE Y2. Results Mean (SD) height velocity (HV) was 8.11 (1.84) and 7.91 (1.84) cm/year at OLE Y1 and Y2, respectively. Mean (SD) height SD score (SDS) was -1.42 (0.90) and -0.95 (0.84) in OLE Y1 and Y2, respectively. In OLE Y1 and Y2, mean change in height SDS (ΔHSDS) was 1.36 and 1.61, respectively, and mean insulin-like growth factor I (IGF-I) SDS remained >1, confirming the efficacy of the treatment. Patients who switched from somatropin to somatrogon had similar HV, height SDS, and ΔHSDS to those who received somatrogon continuously. The incidence of adverse events (all causality) was 71.7% and 72.3% in OLE Y1 and Y2, respectively; most were mild or moderate in severity. Injection site pain and injection site erythema were the most commonly reported treatment-related adverse events in the OLE period. In OLE Y1 and Y2, up to one quarter of patients had IGF-I SDS >2 at two consecutive assessments, meeting protocol criteria for dose reduction. Conclusion Following up to 3 years of somatrogon treatment, children with GHD showed a persistent increase in linear growth velocity compared to baseline. Somatrogon was well tolerated, with no new safety signals identified.
Findings the Hub has extracted
Each claim below is labelled by its type of design and links back to this report.
- Intervention
- Once-weekly somatrogon (long-acting growth hormone) treatment at 0.66 mg/kg/week
- Population
- Children with growth hormone deficiency, with 212 patients in extension year 1 and 177 in extension year 2
Key finding
Mean height velocity sustained at 8.11 cm/year (year 1) and 7.91 cm/year (year 2)