ESPE Abstracts

Background: TransCon human GH (hGH) is a long-acting prodrug of recombinant hGH that releases fully active unmodified hGH. TransCon hGH was shown in phase 1 studies in healthy volunteers and a phase 2 study in adults with hGH deficiency to: i) be safe and well tolerated, ii) provide dose-dependent hGH levels, with same peak level and exposure compared to daily GH, iii) be suitable for a once-weekly dosing regimen, and iv) induce an IGF1 response within the normal range. This ongoing pediatric phase 2 clinical study was designed to investigate safety, efficacy, pharmacokinetics and pharmacodynamics of TransCon hGH compared to daily hGH over a treatment period of 6 months.

Objective and hypotheses: The objective of this study is to investigate i) safety and tolerability, ii) pharmacokinetics and pharmacodynamics, and iii) efficacy of TransCon hGH in children with GH Deficiency (GHD).

Method: Pre-pubertal, treatment naïve GHD children received s.c. injections of one of three once-weekly TransCon hGH doses (0.14, 0.21 and 0.30 mg hGH/kg per week) or daily hGH (Genotropin 0.03 mg hGH/kg per day=0.21 mg/kg per week) over a 6-month treatment period, in a randomized phase 2 study. GHD diagnoses were established in accordance with international consensus guidelines.

Results: In an interim analysis of 25 patients, mean annualized height velocities among the three once-weekly TransCon hGH doses ranged from 11.9 cm for the 0.14 mg/kg per week dose to 14.5 cm for the 0.30 mg/kg per week dose. No safety concerns were observed. Maximum hGH blood concentration was comparable to an equivalent dose of daily hGH, and a dose-proportional increase in IGF1 levels into the normal range was observed.

Conclusion: To date, this phase 2 pediatric study with TransCon hGH in GHD confirms the safety and efficacy profile observed in previous clinical trials. Final data from this pediatric phase 2 study will be presented.

Funding: This study was sponsored by Ascendis Pharma A/S.