Mecasermin

What it is and how it works

Mechanism of Action Insulin-like growth factor-1 (IGF-1) is a key hormonal mediator on statural growth. Under normal circumstances, growth hormone (GH) binds to its receptor in the liver, and other tissues, and stimulates the synthesis/secretion of IGF-1. In target tissues, the Type 1 IGF-1 receptor, which is homologous to the insulin receptor, is activated by IGF-1, leading to intracellular signaling which stimulates multiple processes resulting in statural growth. The metabolic actions of IGF-1 are in part directed at stimulating the uptake of glucose, fatty acids, and amino acids so that metabolism supports growing tissues.

Indications

(mecasermin) injection is indicated for the treatment of growth failure in pediatric patients 2 years of age and older with severe primary IGF- 1 deficiency or with growth hormone (GH) gene deletion who have developed neutralizing antibodies to GH. Limitations of use: INCRELEX is not a substitute to GH for approved GH indications. Severe Primary IGF-1 Deficiency (Primary IGFD) INCRELEX is indicated for the treatment of growth failure in pediatric patients 2 years of age and older with: severe primary IGF-1 deficiency or growth hormone (GH) gene deletion who have developed neutralizing antibodies to GH. Severe Primary IGF-1 deficiency (IGFD) is defined by: height standard deviation score ≤ –3.0 and basal IGF-1 standard deviation score ≤ –3.0 and normal or elevated growth hormone (GH). Limitations of use: INCRELEX is not a substitute to GH for approved GH indications.

Dosage and administration (summary)

should be administered subcutaneously. Injection sites should be rotated to avoid lipohypertrophy. Recommended starting dosage: 0.04 mg/kg to 0.08 mg/kg twice daily. If well-tolerated for at least one week, the dose may be increased by 0.04 mg/kg per dose, to the maximum dose of 0.12 mg/kg given twice daily. Recommended Dosage Treatment with INCRELEX should be supervised by a physician who is experienced in the diagnosis and management of pediatric patients with short stature associated with severe primary IGF-1 deficiency or with growth hormone gene deletion and who have developed neutralizing antibodies to growth hormone. The dosage of INCRELEX should be individualized for each patient.

Contraindications

Known Hypersensitivity to mecasermin Closed Epiphyses Malignant Neoplasia Known Hypersensitivity INCRELEX should not be used by patients who are allergic to mecasermin (rhIGF-1) or any of the inactive ingredients in INCRELEX, or who have experienced a severe hypersensitivity to INCRELEX . Closed Epiphyses INCRELEX should not be used for growth promotion in patients with closed epiphyses.

Warnings and precautions

Hypoglycemia: Severe hypoglycemia leading to hypoglycemic seizures has been observed with INCRELEX treatment. Administer INCRELEX shortly before or after a meal or snack, because it has insulin-like hypoglycemic effects. Hypersensitivity and Allergic Reactions, including Anaphylaxis: A low number of cases indicative of anaphylaxis requiring hospitalization have been reported. Parents and patients should be informed that such reactions are possible and that if a systemic allergic reaction occurs, treatment should be interrupted and prompt medical attention should be sought.

Pregnancy

Pregnancy Risk Summary There are no available data on INCRELEX use in pregnant women. Exposure to INCRELEX during pregnancy is unlikely because the drug is not indicated for use after epiphyseal closure.

Storage and supply

Storage and Handling Before Opening – Vials of INCRELEX are stable when refrigerated at 2° to 8°C (36° to 46°F). Avoid freezing the vials of INCRELEX. Protect from direct light. Expiration dates are stated on the labels.

Source: Mecasermin (Increlex) — US FDA prescribing information, 2026-05-18, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.