Table IV.

Dosing Scenarios and Effects on mAb and L In Vivo Equilibrium

Conditions	Equilibrium favors mAb–L to		Resulting analytes	Comment
	Associate	Dissociate
High mAb/L; high affinity	X		mAbfree, mAbbound, and Lbound	Assumes independent and equivalent binding of L to each of the bivalent binding sites on mAb
mAb/L ∼1; or low affinity		X	Mixed forms	Dosing may increase L to mAb/L ∼1 (16)
High L; slow clearance of L, or increase L production	X		mAbbound, Lbound, and Lfree	L can accumulate if the off rate from mAb is slower than the degradation, resulting in longer T1/2 (17)
Disease status/matrix	Case dependent			Individual matrix variability requires tests on samples from multiple patient donors (18)

mAb monoclonal antibody drugs, L target ligand