TABLE 4

Percentage of unbound fraction in plasma and brain homogenate for three species

Data are presented as means ± S.D.

CompoundPlasmaaBrainb
MouseRatHumanMouseRatHuman
Abemaciclib5.4 ± 0.43.7 ± 0.32.7 ± 0.30.79 ± 0.030.43 ± 0.05ND
Palbociclib23 ± 121 ± 3ND2.0 ± 0.12.7 ± 0.2ND

  • ND, not determined.

  • ↵a Stock solutions of test compounds were added to plasma to give final concentrations of 0.1% DMSO and 1 μM compound.

  • ↵b Brain homogenate was prepared in 100 mM phosphate buffer (1:3 w/v; pH 7.4) by probe sonication.