This is a multicenter, non-randomized, open-label, phase I/II study in children with ACH. This study will start with a dose escalation of ABSK061 in children with ACH to evaluate the safety, tolerability, PK, and efficacy. The RDE confirmation part will evaluate the safety and efficacy of ABSK061 at the recommended doses for expansion (RDEs) in children with ACH. All patients enrolled in the dose escalation part and RDE confirmation part can enter the extended treatment period to further evaluate the long-term safety, tolerability, and long-term efficacy of ABSK061 in children with ACH.
Prior to screening, the guardians and children with ACH (if applicable) must voluntarily provide signed informed consent.
Patients with a clear clinical diagnosis of ACH confirmed by genetic testing for an FGFR3 mutation.
Have completed at least 6 months (i.e., the "Day 181" visit) of growth assessment and observation of natural history of ACH in the observational study (ABSK061-001) before study entry.
Tanner Stage 1 breast development for females or Tanner Stage 1 external genitalia development for males at screening
Known allergy or hypersensitivity to any component of the study drug.
Bone age ≥ 14 years as assessed by the investigator based on hand and wrist X-ray.
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
History or presence of injury or disease of the growth plate(s), other than ACH, that affects growth potential of long bones.