Popis: |
Background: Achondroplasia (ACH) is the most common skeletal dysplasia and the most frequent form of dwarfism. ACH is caused by a gain-of-function mutation in the fibroblast growth factor receptor 3 (FGFR3) gene and results in impairment of the endochondral ossification processes. C-type natriuretic peptide (CNP) promotes chondrocyte development through inhibition of the FGFR3 pathway, specifically through activation of NPRB. CNP is a desirable target as it is known to increase chondrocyte development without off-target effects (Bocciardi, 2007). TransCon CNP is a long-acting prodrug of CNP designed to optimize safety and efficacy with a once-weekly dose. The Phase 1 clinical trial with TransCon CNP demonstrated that doses up to 150 μg CNP/kg were well-tolerated in healthy adult male volunteers, with no clinically significant trends observed in clinical laboratory assessments, vital sign measurements, ECG parameters, or physical examination findings. Methods: The phase 2 ACcomplisH trial will be conducted at over 35 sites worldwide. The primary objective of the trial will be to evaluate the safety and efficacy of once-weekly TransCon CNP compared to placebo at 12 months in prepubertal children, aged 2-10 years old, with ACH. Approximately 60 subjects will be randomized 3:1 to receive either weekly TransCon CNP or placebo. Following screening and verification of clinical ACH with genetic confirmation, subjects will remain within the dose cohort for 52 weeks of treatment. TransCon CNP will be dosed 6 to 100 μg CNP/kg/week across 4 cohorts, with an optional 5th cohort at up to 200 μg CNP/kg/week. An independent Data Monitoring Committee will review safety data prior to initiation of a higher dose cohort. The primary endpoint will evaluate annualized height velocity at 52 weeks of TransCon CNP or placebo. Key secondary endpoints will examine change in upper to lower body segment ratio at week 52, safety, pharmacokinetics (PK), and quality of life associated with weekly TransCon CNP. Conclusion: CNP is targeted specifically to the underlying pathology of ACH through inhibition FGFR3. No effective medicinal product is currently available for the treatment of ACH. TransCon CNP is designed to provide sustained exposure of CNP. This ongoing Phase 2 ACcomplisH trial is designed to assess the efficacy, safety, and PK of TransCon CNP by weekly administration compared to placebo. |