Once-weekly inpegsomatropin versus daily recombinant growth hormone for children with idiopathic short stature

A Multicenter, Randomized, Open-Label, Active-Controlled Phase III Clinical Study to Evaluate the Efficacy and Safety of Inpegsomatropin Injection, s.c Once a Week, Compared With Recombinant Human Growth Hormone (rhGH) Injection in Children With Idiopathic Short Stature (ISS).

This trial will test whether a once-weekly inpegsomatropin injection works as well and is as safe as daily recombinant human growth hormone in prepubertal children with idiopathic short stature.

Quick facts

• Phase: Phase 3
• Study type: Interventional
• Enrollment: 300 (estimated)
• Ages: 3 Years to 11 Years
• Sex: All
• Sponsor: Xiamen Amoytop Biotech Co., Ltd. (Industry-sponsored)
• Locations: 38 sites (Hefei, Anhui and 37 other locations)
• Trial ID: NCT06927310 on ClinicalTrials.gov

What this trial studies

This is a multicenter, randomized, open-label, active-controlled Phase III trial enrolling about 300 prepubertal children with idiopathic short stature. Participants are stratified by sex and age and randomized to receive either once-weekly inpegsomatropin or standard daily recombinant human growth hormone. After a screening period (up to 12 weeks), participants receive 52 weeks of treatment followed by a 5-week safety follow-up. The trial compares growth and safety outcomes between the two treatments to determine if the weekly regimen provides comparable efficacy and tolerability to daily injections.

Who should consider this trial

Good fit: Prepubertal children (boys ≥3 to <11 years with testicular volume <4 mL; girls ≥3 to <10 years with Tanner stage I breasts) with height below −2 SD, bone age within −2 to +1 years of chronological age, BMI between the 5th–95th percentiles, peak GH ≥10 ng/mL, and no prior growth-promoting drug treatment are ideal candidates.

Not a fit: Children who are pubertal, have bone age outside the specified range, have prior systemic growth-promoting treatment, or whose short stature has a known non-idiopathic cause may not benefit from this trial.

Why it matters

Potential benefit: If successful, once-weekly inpegsomatropin could reduce injection frequency while producing similar growth and safety outcomes compared with daily growth hormone.

How similar studies have performed: Other long-acting growth hormone formulations have previously shown comparable growth and safety outcomes to daily growth hormone in clinical trials, so this approach builds on existing evidence.

Eligibility criteria

Inclusion Criteria:

* Prepubertal children: boys aged ≥3 years and \<11 years at screening with testicular volume \<4 mL; girls aged ≥3 years and \<10 years at screening with breast development at Tanner Stage I, i.e., no palpable breast glandular tissue.
* Compared to chronological age, bone age is advanced by no more than 1 year or delayed by no more than 2 years (i.e., -2 years ≤ bone age - chronological age ≤ 1 year).
* Height at screening is below -2 standard deviations (SD) from the mean for age and sex, with height reference to Appendix 1.
* Body mass index (BMI) is within the 5th to 95th percentile for age and sex of healthy 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 ≥1 month), 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 the participants is ≥8 years old, they must also sign the informed consent form. For participants under 8 years old who are able to express their consent, their assent should be clearly documented.

Exclusion Criteria:

* Individuals with closed epiphyses;
* Other types of growth and developmental abnormalities, including confirmed or highly suspected growth hormone deficiency (GHD), Noonan syndrome, Prader-Willi syndrome, Russell-Silver syndrome, Turner syndrome, small for gestational age, short stature due to SHOX gene abnormalities, growth delay due to malnutrition, growth delay due to hypothyroidism, and other short statures with a clear etiology; genetic testing results must be obtained before randomization to exclude short stature caused by definite genetic abnormalities;
* Individuals who have participated in any other clinical trial within 3 months prior to 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 other therapies that may affect growth, including but not limited to methylphenidate, sex hormones, gonadotropin-releasing hormone analogs, aromatase inhibitors, anabolic agents, insulin, etc.;
* Individuals with abnormal liver or kidney function at screening (ALT \> 1.5 times the upper limit of normal, Cr \> upper limit of normal);
* Individuals diagnosed with diabetes mellitus, or with fasting blood glucose ≥6.1 mmol/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 those with congenital anomalies requiring clinical intervention as determined by the investigator;
* Individuals with congenital skeletal abnormalities, or those with scoliosis exceeding 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 hormone or its excipients;
* Individuals with any other disease that the investigator deems may endanger the subject's safety or compromise compliance with the study protocol.

Where this trial is running

Hefei, Anhui and 37 other locations

• Anhui Provincial Children's Hospital — Hefei, Anhui, China (Recruiting)
• The Second Affiliated Hospital of Anhui Medical University — Hefei, Anhui, China (Recruiting)
• Capital Institute of Pediatrics, Beijing (SHOUER) — Beijing, Beijing Municipality, China (Recruiting)
• Children's Hospital of Chongqing Medical University — Chongqing, Chongqing Municipality, China (Recruiting)
• The First Affiliated Hospital of Xiamen University — Xiamen, Fujian, China (Recruiting)
• Gansu Provincial Maternity and Child Care Hospital — Lanzhou, Gansu, China (Recruiting)
• Guangzhou Women and Children's Medical Center — Guangzhou, Guangdong, China (Recruiting)
• Sun Yat-sen Memorial Hospital, Sun Yat-sen University — Guangzhou, Guangdong, China (Recruiting)
• The Third Affiliated Hospital, Sun Yat-sen University — Guangzhou, Guangdong, China (Recruiting)
• Henan Children's Hospital Zhengzhou Children's Hospital — Zhengzhou, Henan, China (Recruiting)
• Wuhan Children's Hospital — Wuhan, Hubei, China (Recruiting)
• Hunan Children's Hospital — Changsha, Hunan, China (Recruiting)
• Children's Hospital Affiliated to Soochow University — Suzhou, Jiangsu, China (Recruiting)
• Jiangxi Provincial Children's Hospital — Nanchang, Jiangxi, China (Recruiting)
• Children's Hospital of Shanghai — Shanghai, Shanghai Municipality, China (Recruiting)
• Chengdu Women's and Children's Central Hospital — Chengdu, Sichuan, China (Recruiting)
• West China Second University Hospital, Sichuan University — Chengdu, Sichuan, China (Recruiting)
• The Affiliated Women's and Children's Hospital of Ningbo University — Ningbo, Zhejiang, China (Recruiting)
• The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University — Wenzhou, Zhejiang, China (Recruiting)
• Sanya Central Hospital — Hainan, China (Recruiting)
• Hangzhou First People's Hospital — Hangzhou, China (Recruiting)
• Zhejiang Provincial People's Hospital — Hangzhou, China (Recruiting)
• The First Affiliated Hospital of Henan University of Science and Technology — Henan, China (Recruiting)
• Jiaxing First Hospital — Jiaxing, China (Recruiting)
• Affiliated Hospital of Jining Medical University — Jining, China (Recruiting)
• Kunming Children's Hospital — Kunming, China (Recruiting)
• Nanjing Children's Hospital — Nanjing, China (Recruiting)
• Qingdao Women and Children's Hospital — Qingdao, China (Recruiting)
• Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine — Shanghai, China (Recruiting)
• Shanghai Children's Medical Center — Shanghai, China (Recruiting)
• Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine — Shanghai, China (Recruiting)
• The First Hospital of Hebei Medical University — Shijiazhuang, China (Recruiting)
• Renmin Hospital of Wuhan University — Wuhan, China (Recruiting)
• The Second Affiliated Hospital of Xi'an Jiaotong University — Xi'an, China (Recruiting)
• Xiangyang Central Hospital — Xiangyang, China (Recruiting)
• The First Affiliated Hospital of Xinjiang Medical University — Xinjiang, China (Recruiting)
• Yuncheng Central Hospital — Yuncheng, China (Recruiting)
• Zhuzhou Central Hospital — Zhuzhou, China (Recruiting)

Study contacts

• Principal investigator: Xiaoping Luo, Ph.D — Tongji Hospital
• Study coordinator: Xiaoping Luo, Ph.D

Conditions Idiopathic Short Stature; Inpegsomatropin Injection; Recombinant Human Growth Hormone Injection