Observing children with achondroplasia over time

A Multicenter, Longitudinal, Observational Study in Children With Achondroplasia

Collecting growth, clinical, and quality-of-life information from children with achondroplasia aged 2.5 to under 11 to see how the condition and treatments affect them over 6 months to 2 years.

Quick facts

• Study type: Observational
• Enrollment: 260 (estimated)
• Ages: 30 Months to 11 Years
• Sex: All
• Sponsor: Abbisko Therapeutics Co, Ltd (Industry-sponsored)
• Locations: 8 sites (Beijing, Beijing Municipality and 7 other locations)
• Trial ID: NCT07301463 on ClinicalTrials.gov

What this trial studies

This is an observational natural history study that will collect anthropometric measurements, clinical characteristics, comorbidities, treatments, and health-related quality of life in children with genetically confirmed achondroplasia. Participants will be followed for at least 6 months and up to 2 years with scheduled visits at pediatric specialty centers. The study enrolls ambulatory children aged ≥2.5 to <11 years who are Tanner Stage 1 and collects data to characterize growth patterns, complications, and treatment use. No investigational interventions are administered as part of this observation.

Who should consider this trial

Good fit: Children aged ≥2.5 to <11 years with achondroplasia confirmed by FGFR3 genetic testing who are ambulatory, Tanner Stage 1, and whose guardians can provide consent are ideal candidates.

Not a fit: Children with closed growth plates or bone age ≥14, those with other forms of skeletal dysplasia or conditions causing short stature, or non-ambulatory children are unlikely to benefit from this natural history observation.

Why it matters

Potential benefit: If successful, the study could improve understanding of growth patterns and complications in achondroplasia and help guide future treatments and care recommendations.

How similar studies have performed: Other natural history studies and drug trials for achondroplasia (for example, CNP-analog therapies) have shown measurable effects on growth, but oral ABSK061 represents a novel approach with limited published data.

Eligibility criteria

Inclusion Criteria:

1. Prior to screening, the guardians and children with ACH (if applicable) must be willing and able to provide signed informed consent.
2. Clinical diagnosis of ACH confirmed FGFR3 mutation by genetic testing.
3. Male or female aged ≥2.5 to \<11 years old at screening.
4. Tanner Stage 1 breast development for females or Tanner Stage 1 external genitalia development for males at screening.
5. Ambulatory and able to stand without assistance.

Exclusion Criteria:

1. Bone age ≥14 years as assessed by the investigator based on hand and wrist X-ray taken within 6 months prior to Day 1.
2. Current evidence of growth plate closure (proximal tibia, distal femur), or AGV ≤ 1.5 cm/year over a period ≥6 months prior to screening.
3. Have a form of skeletal dysplasia other than ACH or known medical conditions that result in short stature or abnormal growth, including but not limited to severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN), Turner syndrome, pseudoachondroplasia, inflammatory bowel disease, chronic renal insufficiency, active celiac disease a, Vitamin D deficiency b, untreated hypothyroidism c, poorly controlled diabetes (HbA1c ≥8.0%) or diabetic complications d.

   1. Celiac disease responsive to a gluten-free diet is allowed
   2. Vitamin D deficiency or insufficiency with a 25-hydroxyvitamin D \[25- (OH) D\] level ≥ 30 nmol/L after supplementation is allowed. Vitamin D deficiency is defined as 25-(OH) D level \<30 nmol/L. Vitamin D insufficiency is defined as 25-(OH) D level 30\~50 nmol/L. Patients with Vitamin D deficiency or insufficiency must be on Vitamin D regimen prior to screening
   3. Patients with hypothyroidism meeting the following criteria are allowed to enroll: must be clinically euthyroid for one month prior to screening and, in the opinion of the investigator, have achieved any catch-up growth expected from thyroxine replacement
   4. Patients with diabetes must have been on stable medication regimen for 3 months prior to screening
4. History or presence of injury or disease of the growth plate(s), other than ACH, that affects growth potential of long bones.
5. Impaired cardiac function or clinically significant cardiovascular disease, including any one of the following: New York Heart Association class II or higher heart disease, congenital heart disease (patients with repaired uncomplicated patent ductus arteriosus or atrial/ventricular septal defect with repair are allowed), clinically significant arrhythmias requiring therapy, aortic regurgitation, congestive heart failure, or any other uncontrolled heart disease.
6. For ACH-related complications: Current severe sleep apnea, symptomatic and/or requiring intervention for hydrocephalus, or spinal cord compression at the cranio-cervical junction, and has previously undergone ventriculoperitoneal shunt surgery.
7. Bone fracture within 6 months prior to screening (within 2 months for finger and toe fractures).
8. Have received any dose of medications affecting stature or body proportionality, such as human growth hormone, insulin-like growth factor 1 (IGF-1), or anabolic steroids within 3 months prior to screening, or long-term treatment (\>3 months) with the above drugs at any time.
9. Prior treatment with any CNP analogues or FGFR inhibitors. Prior use of any investigational drugs or investigational medical devices that affect stature or body proportionality.
10. Any comorbidities, disease or condition that, in the opinion of the investigator, may make the patient unlikely to fully complete the study-related procedures, may affect protocol compliance.

Where this trial is running

Beijing, Beijing Municipality and 7 other locations

• Beijing Children's Hospital, Capital Medical University — Beijing, Beijing Municipality, China (Recruiting)
• Guangzhou Women and Childrens Medical Center — Guangzhou, Guangzhou, China (Not_yet_recruiting)
• Henan Children's Hospital, Zhengzhou Children's Hospital — Zhengzhou, Henan, China (Not_yet_recruiting)
• Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology — Wuhan, Hubei, China (Recruiting)
• Xin Hua Hospital Affiliatod to Shanghai Jiao Tong University School of Medicine — Shanghai, Shanghai Municipality, China (Recruiting)
• Chengdu Women's and Children's Central Hospital — Chengdu, Sichuan, China (Not_yet_recruiting)
• West China Second University Hospital, Sichuan University — Chengdu, Sichuan, China (Active_not_recruiting)
• Children's Hospital Zhejiang University School of Medicine — Hangzhou, Zhejiang, China (Not_yet_recruiting)

Study contacts

• Study coordinator: Jing Zhang

Conditions Achondroplasia