Dose-response relationship: Relevance for clinical use

Dose-finding studies are performed routinely in patients and - if appropria te surrogate models exist also in healthy volunteers. Such studies aim at e stablishing the optimal dose range for further clinical studies on the effi cacy and the risk-benefit ratio of a new drug. The dose-reponse relationship of a drug is most often described by a sigmoi dal curve. Its parameters include the mean effective dose, the maximal effe ct and the steepness. Interpretation of such curves should be done in the c ontext of the intended clinical indications of the drug. The risk-benefit ratio of a drug can be assessed by overlapping the dose-re sponse curve of wanted and unwanted clinical effects, again, any overlappin g (which can be described e. g. by the therapeutic index) should be seen in the context of the indication and available therapeutic alternatives.