Growth Outcomes and Safety of Recombinant Growth Hormone in Noonan Syndrome: A Systematic Review and Meta-Analysis

Noonan syndrome (NS), a RASopathy marked by partial resistance within the GH-IGF-1 axis, is characterised by short stature. Although growth hormone is commonly prescribed, there is a gap in data on long-term efficacy and safety profile. The objective of this study was to assess the long-term growth response and safety profile of recombinant human growth hormone (rhGH) therapy in children with NS. Randomised and observational studies reporting height outcomes in children with NS treated with rhGH were included. Thirty-nine studies, including 3167 patients, were analysed. At baseline, children had marked growth impairment [mean height standard deviation score (SDS) -2.95]. After 1 year of therapy, height SDS increased significantly (mean change +1.16). rhGH therapy leads to meaningful and sustained improvements in linear growth in children with NS without major safety concerns. Early initiation and continuation of therapy, alongside regular cardiac monitoring, should be considered in clinical practice.