Our manuscript “A quantitative modeling framework to understand the physiology of the hypothalamic-pituitary-adrenal axis and interaction with cortisol replacement therapy “ by Bindellini et al. has been published online in the Journal of Pharmacokinetics and Pharmacodynamics, and is now online available. In continuation of our work from Johanna, Davide expanded her hydrocortisone pharmacokinetic model to include endogenous ACTH and cortisol, allowing to study the impact of disease and therapy on the endogenous system. His work continues the collaboration with our partners from Charité-Univeristätsmedizin Berlin and University of Sheffield.