Quantitative systems pharmacology (QSP)

Quantitative systems pharmacology couples pharmacokinetics with mechanistic models of signalling pathways, cell populations and organ systems. In oncology it has been used to predict the exposure-response of checkpoint inhibitors, to design bispecific and CAR-T dosing that limits cytokine release, to simulate resistance to targeted drugs and to support regulatory submissions under the FDA's model-informed drug development programme. Project Optimus, the FDA's 2021 initiative to end maximum-tolerated-dose defaults for targeted drugs, leans on these models to justify lower doses.