Pegylated Long-Acting Human Growth Hormone Is Well-Tolerated in Healthy Subjects and Possesses a Potential Once-Weekly Pharmacokinetic and Pharmacodynamic Treatment Profile

Background: Recombinant human GH (rhGH) is usually administered as a daily sc injection, which may be both inconvenient and distressing for patients. NNC126-0083 is a pegylated rhGH developed with the aim of reducing serum clearance and thereby prolonging the exposure leading to once-weekly sc administration. Objectives: In this first human dose trial, the safety, tolerability, pharmacokinetics, and pharmacodynamic parameters of a single administration of NNC126-0083 were evaluated. Subjects and Methods: Seven groups of eight healthy male volunteers were dosed once with a single sc administration of NNC126-0083 (n = 6) or placebo (n = 2). The doses were escalated between the cohorts in a sequential mode. Blood samples for assessment of safety, pharmacokinetics, and pharmacodynamic response (IGF-I, IGF binding protein-3, free IGF-I) as well as GH binding protein were taken up to 240 h after dosing. Results: Seven doses of NNC126-0083 were administered. After NNC126-0083 administration, a significant deviation from pharmacokinetic dose proportionality was observed for the highest doses. A strong dose-dependent pharmacodynamic response was seen with elevated levels of IGF-I and IGF binding protein-3 for all doses administered. The elevation was maintained for more than 1 wk for the highest doses. All doses of NNC126-0083 were well tolerated. No local tolerability issues were identified. Conclusion: After a single sc administration of NNC126-0083 in healthy male volunteers, a sustained dose-dependent pharmacodynamic response was induced. These results indicate that NNC126-0083 has the potential for an efficacious, well-tolerated, once-weekly rhGH compound in the treatment of GH deficiency in adults. (J Clin Endocrinol Metab 95: 3411-3417, 2010)