Phase 3 Study to Evaluate the Efficacy and Safety of Human Growth Hormone Injection (Sinotropin AQ) for the Treatment of Children With Idiopathic Short Stature

A Multicenter, Randomized, Open-Label, Active-Controlled, Non-Inferiority Phase 3 Study to Evaluate the Efficacy and Safety of Human Growth Hormone Injection (Sinotropin AQ) for the Treatment of Children With Idiopathic Short Stature (ISS)

This study is a multicenter, randomized, open-label, active-controlled, non-inferiority Phase III clinical trial. It aims to evaluate the efficacy and safety of Human Growth Hormone (hGH) Injection (Sinotropin AQ) in pediatric participants with Idiopathic Short Stature (ISS). Eligible participants will be randomized to receive either the study drug or an active comparator for 52 weeks. The primary efficacy endpoint is height velocity (HV, cm/year) over the treatment period. The study drug will be administered subcutaneously once daily at a dose of 0.15 IU/kg. The results of this trial will provide evidence on whether hGH Injection represents an effective and safe treatment option for improving height in children with ISS.

Inclusion Criteria:

• 1. Tanner stage I (prepubertal) at informed consent: males aged 3 to <11 years ; females aged 3 to <10 years ;
• 2. At screening, height < -2 standard deviations (SD) for age and sex (height reference per Appendix 1);
• 3. Peak GH ≥10.0 ng/mL in any growth hormone (GH) stimulation test;
• 4. Bone age minus chronological age ≤ 1 year.

Exclusion Criteria:

• 1.Closed epiphyses (skeletally mature)；
• 2.Severe allergic diathesis, or known hypersensitivity to growth hormone or any of its excipients；
• 3.History of malignancy or current active malignancy；
• 4.Systemic chronic diseases, including but not limited to moderate-to-severe anemia, hypothyroidism, chronic kidney disease, cardiovascular disease (e.g., dilated cardiomyopathy), psychiatric disorders, or congenital anomalies that require clinical intervention per the investigator's judgment.
• 5.Patients with a prior diagnosis of intracranial hypertension;
• 6.Patients with congenital skeletal dysplasia, or scoliosis ≥15° (or moderate or greater), limping (gait disturbance), and patients with a prior diagnosis of slipped capital femoral epiphysis ;
• 7.Other types of growth and developmental disorders, including confirmed or highly suspected growth hormone deficiency (GHD), Noonan syndrome, Prader-Willi syndrome, Russell-Silver syndrome, Turner syndrome, small for gestational age (SGA), short stature due to SHOX gene defects, and short stature of other identified causes;
• 8. Patients with a confirmed diagnosis of diabetes mellitus, or fasting blood glucose ≥6.1 mmol/L on two consecutive measurements.