The Efficacy and Safety of Inpegsomatropin Injection in Children With Turner Syndrome (TS) and Short Stature

• Inpegsomatropin-Injection (Drug): Inpegsomatropin injection, 280 μg/kg/week, s.c., once weekly, for 52 weeks.
• Givopegsomatropin Solution Injection (Drug): Givopegsomatropin Solution Injection, 200 μg/kg/week, s.c., once weekly, for 52 weeks.

Primary outcomes

• Growth velocity (HV, cm/year). [Week 52]

Secondary outcomes

• Change in height standard deviation score from baseline (△HT SDS) [From baseline to all follow-up time points at Week 52]
• Change in height velocity from baseline (△HV) [From baseline to all follow-up time points at Week 52]
• Change in insulin-like growth factor 1 standard deviation score from baseline (△IGF-1 SDS) [From baseline to all follow-up time points at Week 52]
• Ratio of change in bone age from baseline to change in chronological age from baseline (△BA/△CA) [Week 52]

Sex: Female, ages: 2 Years to 12 Years

Inclusion Criteria:

* Prepubertal girls at Tanner stage I, with age ≥ 2 years and < 12 years at the time of informed consent signature.
* With clinical manifestations of Turner syndrome and a confirmed diagnosis of Turner syndrome based on peripheral blood karyotype analysis (karyotype analysis of at least 30 metaphase cells).
* At screening, bone age is delayed relative to chronological age or advanced by no more than 1 year (i.e., bone age - chronological age ≤ 1 year).
* At screening, height is below -2 standard deviations (-2SD) of the mean for age and gender; height reference is shown in Appendix 1.
* No prior systematic pharmacological growth-promoting treatment (continuous use for ≥ 1 month), including but not limited to growth hormone, insulin-like growth factor 1 (IGF-1), etc.
* Thyroid hormone replacement therapy (if applicable) received prior to randomization should be maintained on a stable regimen for at least 4 weeks.
* The legal guardian understands and signs the informed consent form; participants aged ≥ 8 years shall also sign the informed consent form. For participants aged under 8 years who are capable of expressing assent, their assent shall be clearly documented.

Exclusion Criteria:

* Subjects with closed epiphyses.
* Patients with Turner syndrome carrying Y chromosome or Y-chromosome-derived fragments and without gonadectomy.
* Other types of growth and development abnormalities, including but not limited to growth hormone deficiency (GHD), Noonan syndrome, Prader-Willi syndrome, and growth retardation caused by malnutrition.
* Participation in any other clinical trial within 3 months prior to screening with pharmacological or non-pharmacological intervention received.
* Inhaled glucocorticoids used continuously for more than 2 weeks, or oral/intravenous glucocorticoids used continuously for more than 1 week within 3 months prior to screening.
* Receiving other treatments that may affect growth, including but not limited to methylphenidate, sex hormones, gonadotropin-releasing hormone analogs, aromatase inhibitors, anabolic agents, etc.
* Abnormal liver and renal function at screening (ALT > 2 times the upper limit of normal; Cr > upper limit of normal).
* Subjects with abnormal glucose metabolism, including: a. Diagnosed diabetes mellitus; b. Fasting blood glucose ≥ 6.1 mmol/L on two consecutive measurements; c. Glycated hemoglobin (HbA1c) ≥ 6.5%; d. Impaired glucose tolerance judged by the investigator as unsuitable for participation in this study.
* Presence of chronic infectious diseases judged by the investigator to interfere with study participation, such as chronic hepatitis B.
* Subjects with systemic chronic diseases, such as chronic kidney disease, severe cardiovascular diseases (e.g., aortic dissection, uncontrolled hypertension), psychiatric and psychological disorders.
* Subjects with severe congenital skeletal dysplasia; or those with scoliosis > 20°, significant kyphosis, claudication, or a prior diagnosis of slipped capital femoral epiphysis.
* Subjects with a prior history of intracranial hypertension.
* Subjects with a history of malignant tumor or current active malignant tumor, including intracranial tumors.
* Known hypersensitivity to growth hormone or its excipients.
* Subjects with celiac disease who have not maintained a gluten-free diet within 12 months prior to screening.
* Any other conditions deemed inappropriate for enrollment in this clinical trial by the investigator.

• Xiaoping Luo, Principal investigator, Tongji Hospital