Pharmacyclics’ (now AbbVie) Imbruvica (ibrutinib) is an anticancer drug targeting B-cell malignancies. Leveraging the US FDA’s accelerated approval programs, the company generated PBPK models using the Simcyp Simulator to inform dose, dosing regimens, and DDIs. Approved initially for mantle cell lymphoma as a breakthrough therapy, Imbruvica is now approved for multiple uses, including first-line CLL.