Safety of Growth Hormone Treatment of Children with Idiopathic Short Stature: The US Experience

Recombinant human growth hormone (rhGH) is approved in the United States for treatment of idiopathic short stature (ISS). The occurrence of adverse events (AEs) and the long-term safety of rhGH treatment in this patient population are reviewed. Data were analyzed from postmarketing surveillance studies that included ISS patients, prospective ISS treatment trials and studies of specific AEs in smaller groups of rhGH-treated children. Frequency rates of targeted AEs (i.e., scoliosis, slipped capital femoral epiphysis, intracranial hypertension, pancreatitis) in patients with ISS are similar to or lower than the rates observed in other rhGH-treated conditions. At dosages of 0.24-0.37 mg/kg/week, rhGH treatment in children with ISS does not adversely affect blood glucose levels. At dosages ≥ 0.3 mg/kg/week, a dose-dependent increase in mean fasting and stimulated insulin levels is observed. Current evidence derived from 'on-treatment' surveillance studies suggests that rhGH does not increase the risk for new malignancies in children with ISS.The safety profile of rhGH at doses ≤ 0.37 mg/kg/week for the treatment of children with ISS is similar to or better than the profile seen in other rhGH-treated conditions and is not associated with any predictable AEs. Due to a continuing trend toward dose escalation to achieve greater height-promoting effects and the possibility of delayed post-treatment effects of hyperinsulinemia and/or heightened GH and insulin-like growth factor I exposure on cancer risk, caution and ongoing scrutiny of risks versus benefits are warranted.