This human clinical study developed a pharmacokinetic-pharmacodynamic model to characterize how ipamorelin, a growth hormone-releasing peptide, is absorbed, distributed, and produces effects in the body following administration to healthy volunteers. The modeling approach integrated drug concentration measurements with observed growth hormone responses to predict the relationship between ipamorelin dose and biological effect. This research provides quantitative data on ipamorelin’s time-concentration profile and growth hormone stimulation patterns in humans (human clinical evidence level).