Table of Contents
- Clinical trials overview
- Phase 2 trial in children with achondroplasia
- Phase 3 trial in children with short stature or growth failure
- Key endpoints and measures
- Who these trials are for
Clinical trials overview
Two authorised interventional studies are investigating Lonapegsomatropin in children with growth-related conditions.[1][2] One study is Phase 2 and one is Phase 3, so the research includes both an earlier and a later stage of testing.[1][2]
These trials are designed to learn whether Lonapegsomatropin can improve growth, and to check safety and tolerability in the study groups.[1][2] The target populations are children with achondroplasia and children with several growth hormone sufficient disorders linked to short stature or growth failure.[1][2]
Phase 2 trial in children with achondroplasia
The first study is COACH, a Phase 2, open-label, single-arm, 156-week trial in children with achondroplasia.[1] Open-label means everyone knows what treatment is being given, and single-arm means there is only one treatment group.[1]
This study is authorised and plans to enroll 18 children.[1] It is studying combined once-weekly navepegritide and Lonapegsomatropin, with the goal of comparing growth effects against navepegritide alone and checking the safety profile of the combination.[1]
The main outcome is annualized growth velocity at Week 52, which means how much height growth happens over one year.[1] The study also measures treatment-emergent adverse events, which are health problems that appear after treatment begins.[1]
Phase 3 trial in children with short stature or growth failure
The second study is a Phase 3 trial that compares weekly Lonapegsomatropin with daily somatropin in children and adolescents with short stature or growth failure due to growth hormone sufficient disorders.[2] The listed conditions are Turner syndrome, idiopathic short stature, SHOX deficiency, and small for gestational age.[2]
This study is also authorised and plans to enroll 186 participants.[2] It is designed to evaluate the efficacy and safety of Lonapegsomatropin compared with somatropin, which means the researchers want to see how well the treatments work and how safe they are in the study population.[2]
The main outcome is annualized height velocity at Week 52.[2] This is a standard way to measure growth in children and shows how much height is gained in one year.[2]
Key endpoints and measures
Both trials focus on growth outcomes, which are called endpoints in clinical research.[1][2] An endpoint is the main result the researchers want to measure to answer the study question.[1][2]
In the achondroplasia study, the main growth endpoint is AGV at Week 52, along with safety outcomes such as TEAEs.[1]
In the Phase 3 study, the main endpoint is AHV at Week 52, comparing Lonapegsomatropin with daily somatropin.[2]
These outcomes help show whether treatment can support better growth over time and whether the treatment can be used safely in the studied children.[1][2]
Who these trials are for
The Phase 2 study is for children with achondroplasia, a condition that affects bone growth and often leads to short stature.[1]
The Phase 3 study is for children and adolescents with Turner syndrome, idiopathic short stature, SHOX deficiency, or small for gestational age.[2] These groups were chosen because they have growth problems that the study is trying to address.[2]
Because the trials have different designs and target groups, the results will help answer different questions about Lonapegsomatropin in pediatric growth care.[1][2]




