Resolving parameter non-identifiability through hypothesis testing with PBPK simulations: identifying solubility-limited absorption (reference 2). PBPK physiologically based pharmacokinetics, NCE new chemical entity, SAD single ascenting dose, MAD multiple ascending dose, FASSIF fasted simulated small intestinal fluid, IV intravenous, PK pharmacokinetics, AUC area under the curve, CLint intrinsic clearance, CYP cytochrome P450, Kp tissue partition coefficient