Table III.

Final Pharmacokinetic Model-Estimated Parameters

Parameter (units)	Description	Estimate (CV%)
Vc(L·kg−1) a	Central volume of distribution	1.4×10−1 (7)
kel(min−1· kg−1)a	Elimination rate constant for free exenatide	3.2×10−2 (8)
kpt (min−1)	Distribution rate constant	2.6 × 10−2 (15)
ktp (min−1)	Distribution rate constant	2.7 × 10−2 (8)
kdeg (min−1)	Degradation rate constant for free receptor	1.55 × 100 (18)
kint (min−1)	Rate constant of internalization for   exendine-4-receptor complex	2.3 × 10−3 (41)
kon(pM−1 ·min−1)	Second-order association rate constant	1.7×10−5 (8)
Koff_mouse (min−1)	First-order dissociation rate constant	2.3 × 10−4 (52)
Koff_rat (min−1)		5.2 × 10−5 (46)
Koff_monkey (min−1)		1.5×10−3 (58)
${\mathrm{R}}_{\text{tot\_}}^0\text{mouse}$ (pM)	Receptor concentration at baseline	1.0× 103 (N/A)b
${\mathrm{R}}_{\text{tot\_}}^0\text{rat}$ (pM)		5.2 × 103 (N/A)b
${\mathrm{R}}_{\text{tot\_}}^0\text{monkey}$ (pM)		5.2 × 102 (N/A)b
Vmax_mouse (pmol·min−1)	Maximum absorption rate	8.3 × 101 (45)
Vmax_rat (pmol·min−1)		2.4 × 102 (19)
Vmax_monkey (pmol·min−1)		5.8 × 102 (62)
Km_mouse (pmol) Km_rat (pmol)	Amount of exenatide when absorption rate is half maximal	9.1 × 102 (61) 3.4 × 104 (24)
Km_monkey (pmol)		1.8 × 104 (74)

^aValue represents an allometric coefficient scaled to body weight

^bNot applicable; fixed value