In contrast to the pkCSM predictions it was found that 38 had no significant inhibition of any of the five CYPs tested in this panel (Table ). Alternatively, we sought to assess the potential for metabolic modification of the molecule by quantifying stability in human liver microsomes (HLM). It was found that compound 38 is metabolized in the HLM assay with 88% of molecule remaining at the 15-minute time-point followed by steady decline to 45% remaining at the 60-minute timepoint. This analysis yielded a half-life (t1/2) of approximately 51 minutes and intrinsic clearance (Clint) of 136.7 µL/min/mg (Table ). On the basis of the physicochemical, in vitro pharmacokinetic properties and relatively benign safety profile against off-targets for analog 38 we chose to move this molecule forward for testing in the mechanical allodynia mouse model.