The Efficacy and Safety of Inpegsomatropin Injection in Children With Idiopathic Short Stature

Inclusion Criteria:

• Prepubertal children: boys aged ≥3 years and <11 years at screening with testicularvolume <4 mL; girls aged ≥3 years and <10 years at screening with breast developmentat Tanner Stage I, i.e., no palpable breast glandular tissue.

• Compared to chronological age, bone age is advanced by no more than 1 year ordelayed by no more than 2 years (i.e., -2 years ≤ bone age - chronological age ≤ 1year).

• Height at screening is below -2 standard deviations (SD) from the mean for age andsex, with height reference to Appendix 1.

• Body mass index (BMI) is within the 5th to 95th percentile for age and sex ofhealthy children, with reference to Appendix 2.

• Peak GH level ≥10.0 ng/ml in at least one GH stimulation test.

• No prior systemic pharmacological treatment for growth promotion (continuous use ≥1month), including but not limited to growth hormone, insulin-like growth factor 1 (IGF-1), etc.

• The legal guardian understands and signs the informed consent form. If theparticipants is ≥8 years old, they must also sign the informed consent form. Forparticipants under 8 years old who are able to express their consent, their assentshould be clearly documented.

Exclusion Criteria:

• Individuals with closed epiphyses;

• Other types of growth and developmental abnormalities, including confirmed or highlysuspected growth hormone deficiency (GHD), Noonan syndrome, Prader-Willi syndrome,Russell-Silver syndrome, Turner syndrome, small for gestational age, short staturedue to SHOX gene abnormalities, growth delay due to malnutrition, growth delay dueto hypothyroidism, and other short statures with a clear etiology; genetic testingresults must be obtained before randomization to exclude short stature caused bydefinite genetic abnormalities;

• Individuals who have participated in any other clinical trial within 3 months priorto screening and have received pharmacological or non-pharmacological interventions;

• Individuals who received inhaled corticosteroids for more than 2 consecutive weeks,or oral or intravenous corticosteroids for more than 1 consecutive week, within the 3 months prior to screening;

• Individuals who are currently receiving or require long-term treatment with othertherapies that may affect growth, including but not limited to methylphenidate, sexhormones, gonadotropin-releasing hormone analogs, aromatase inhibitors, anabolicagents, insulin, etc.;

• Individuals with abnormal liver or kidney function at screening (ALT > 1.5 times theupper limit of normal, Cr > upper limit of normal);

• Individuals diagnosed with diabetes mellitus, or with fasting blood glucose ≥6.1mmol/L on two consecutive occasions;

• Individuals with chronic infectious diseases, such as chronic hepatitis B;

• Individuals with systemic chronic diseases, such as moderate to severe anemia,malnutrition, hypothyroidism, chronic kidney disease, cardiovascular diseases (e.g.,dilated cardiomyopathy, etc.), psychiatric and psychological disorders, or thosewith congenital anomalies requiring clinical intervention as determined by theinvestigator;

• Individuals with congenital skeletal abnormalities, or those with scoliosisexceeding 15°, limping, or a history of slipped capital femoral epiphysis;

• Individuals with a history of increased intracranial pressure;

• Individuals with a history of malignancy or currently having active malignancy,including intracranial tumors;

• Individuals with severe allergic constitutions, or known allergies to growth hormoneor its excipients;

• Individuals with any other disease that the investigator deems may endanger thesubject's safety or compromise compliance with the study protocol.