Mecasermin

Mecasermin is a recombinant human insulin-like growth factor-1 (rhIGF-1) used to treat growth failure in children with severe primary IGF-1 deficiency or with IGF-1 deficiency due to Laron syndrome. It acts by binding to the IGF-1 receptor to promote growth and anabolic effects. It is not indicated for growth failure caused by growth hormone deficiency.

Medical uses and indications: Mecasermin is indicated for pediatric patients with severe primary IGF-1 deficiency or Laron syndrome who have evidence of IGF-1 deficiency and have had an inadequate response to growth hormone therapy. It is intended to address the underlying IGF-1 deficiency rather than GH signaling.

Administration and dosing: Mecasermin is given by subcutaneous injection twice daily. The usual starting dose is about 0.04 mg/kg per day, divided into two doses, with gradual increases in 0.04 mg/kg/day increments every 1–2 weeks to a maximum of 0.12 mg/kg/day, guided by growth response and tolerability. Dosing should be taken with meals or shortly after to reduce the risk of hypoglycemia, and dietary management may be advised around dosing times.

Adverse effects and monitoring: The most important safety concern is hypoglycemia, so glucose monitoring and appropriate meal or snack timing around doses are essential. Other common adverse events include injection-site reactions, headaches, lymphadenopathy, tonsillar/adenoidal hypertrophy, fever, and abdominal discomfort. Clinicians monitor growth response and adverse effects, adjusting dose as needed. Mecasermin should be avoided in individuals with hypersensitivity to IGF-1 or with active malignant disease, and caution is advised in patients with poorly controlled diabetes or other conditions increasing hypoglycemia risk.

Regulatory status: Mecasermin is approved for pediatric use in several regions under brand names such as Increlex, with varying dosing recommendations and monitoring requirements. A longer-acting combination product combining IGF-1 with IGF-binding protein-3 has been explored in some markets.