The US Food and Drug Administration (FDA) has approved lonapegsomatropin for treatment of growth hormone deficiency (due to inadequate secretion of endogenous growth hormone) in children aged ≥1 year and weighing at least 11.5 kg.  

The approval is based on the phase III heiGHt trial conducted in treatment-naïve children published in July in the Journal of Clinical Endocrinology & Metabolism. Results of the trial showed that children treated with lonapegsomatropin grew by 4.4 inches per year versus children treated with somatropin injections, who grew 4.1 inches per year.

• Dosage and administration: 0.24 mg/kg body weight once-weekly subcutaneously into the abdomen, buttock, or thigh with regular rotation of the injection sites
• Dosage forms: lyophilized powder available in single-dose, dual-chamber, prefilled cartridges containing lonapegsomatropin-tcgd
• Strengths available: 3 mg, 3.6 mg, 4.3 mg, 5.2 mg, 6.3 mg, 7.6 mg, 9.1 mg, 11 mg, 13.3 mg
• Contraindications: Hypersensitivity to somatropin or any of the excipients, acute critical illness, active malignancy, active proliferative or severe non-proliferative diabetic retinopathy, severely obese children with Prader-Willi syndrome or those children who have severe respiratory impairment
• Side effects: Fever, cough, nausea and vomiting, hemorrhage, diarrhea, abdominal pain, arthralgia, arthritis
• Warnings and precautions: Progression or recurrence of pre-existing tumors, unmasking of glucose intolerance and diabetes and hypothyroidism, fluid retention, monitor thyroid hormones for hypothyroidism control, rule out papilledema (sign of intracranial pressure)

(Source: US FDA Skytrofa Prescribing Information; FDA approves first once-weekly growth hormone for children - Medscape - Sep 02, 2021)