Ascendis Pharma has announced positive topline results from a Phase III trial investigating TransCon hGH (lonapegsomatropin) in adults with GHD.

The Phase III foresiGHt trial (NCT04615273) enrolled 259 adults with GHD aged 23 to 80 years old across approximately 120 sites in North America, Europe, Asia, and Oceania.

TransCon hGH, which is marketed as Skytrofa for the paediatric patient population, demonstrated a statistically significant reduction from baseline in trunk fat and an increase in total body lean mass (LS) at week 38 compared to the placebo.

The trial recorded an LS mean difference of -2.04% from baseline in trunk per cent fat as measured by dual X-ray absorptiometry between the treatment and placebo cohorts. In secondary endpoints, there was an LS mean difference of 1.7kg from the baseline of total body lean mass.

Phase III trial design

foresiGHt is a Phase III parallel-arm, placebo-controlled (double-blind) and active-controlled (open-label) trial to compare the efficacy and safety of TransCon hGH with placebo and daily human growth hormone (HGH) in adults with GHD. The trial is due to end in December 2024.

Patients were randomised in a ratio of 1:1:1 to receive TransCon hGH, placebo, or daily HGH, based on age and oral oestrogen intake, with an approximately equivalent intake of HGH for TransCon hGH and daily HGH.

TransCon hGH was generally safe and well tolerated, with no discontinuations related to the study drug. The asset had a comparable safety and tolerability profile to daily doses of hGH.

Exploratory post-hoc analysis suggests TransCon hGH has the same treatment effects on target tissues as daily hGH.

Ascendis plans to submit a supplemental biologics licence application to the FDA next year.

TransCon was first approved in 2021 for the paediatric patient population. At the time, it was the first and only FDA-approved once-weekly treatment for paediatric GHD.

According to GlobalData’s Pharmaceutical Intelligence Center, Ascendis currently has six ongoing clinical trials with TransCon. This includes a Phase II trial (NCT05690386), which is evaluating the candidate in Turner syndrome patients.

Turner syndrome is a condition that affects female patients and can cause medical and developmental problems, including short height, issues with ovary development and heart defects.

GlobalData predicts a global sales forecast for TransCon hGH of $720m in 2029.

GlobalData is the parent company of the Clinical Trials Arena.