Fig. 1

An example of a trajectory of compounds from hit identification to clinical candidate. The white circles and lines (dotted one: hit to lead, and solid one: lead optimization) represent the compound and the trajectory of compound optimization. The X- and Y- axis represent the value of parameters which are better if the values are larger. It can be seen that multiple properties matter in optimization (where in particular the X-axis subsumes a large number of additional properties), and that optimization is usually not linear in practice