The goal of this study is to further characterise the potential long-term safety risks of lonapegsomatropin in patients treated with lonapegsomatropin under real-world conditions in the post-marketing setting.

Inclusion Criteria:

• Paediatric patients with GHD who are on treatment with lonapegsomatropin
• Patients being clinically managed in Europe or the USA
• Appropriate written informed consent/assent as applicable for the age of the patient
• Patients willing to comply with follow-up requirements of the study

Exclusion Criteria:

• Patients participating in any interventional clinical trial for short stature
• Patients being treated with a GH or IGF-1 therapy, other than lonapegsomatropin, at enrollment
• Patients for whom treatment with lonapegsomatropin is contraindicated
• Patients with closed epiphyses
• Patients with active malignant tumours
• Patients under antitumour therapy within the past 12 months prior to instituting GH therapy
• Hypersensitivity to somatropin or any of the excipients in lonapegsomatropin

Patients from centres in Europe and the USA will be eligible for enrollment into the study.

Patients may be enrolled in the study if they are on treatment with lonapegsomatropin. The decision to treat the patient with lonapegsomatropin will be made prior to and independently of the decision to invite the patient to enroll into the study. Both patients naïve to GH treatment and patients previously treated with GH therapy will be eligible for enrollment.