Table 4

In vivo PK studies
Category Name Description Unit reference
PK parameters AUCinf Area under the drug concentration time curve. mg h L-1 RT p37
AUCSS Area under the drug concentration time curve within a dosing curve at steady state. mg h L-1 RT pxi
AUCt Area under the drug concentration time curve from time 0 to t. mg h L-1 RT p37
AUMC Area under the first moment of concentration versus time curve. mg2 h L-2 RT p486
AUCR AUC ratio (drug interaction parameter). Unit free
CL Total clearance is defined as the proportionality factor relating rate of drug elimination to the plasma drug concentration. ml h-1 RT p23
CLb Blood clearance is defined as the proportionality factor relating rate of drug elimination to the blood drug concentration. ml h-1 RT p160
CLu Unbound clearance is defined as the proportionality factor relating rate of drug elimination to the unbounded plasma drug concentration. ml h-1 RT p163
CLH Hepatic portion of the total clearance. ml h-1 RT p161
CLR Renal portion of the total clearance. ml h-1 RT p161
CLpo Total clearance of drug following an oral dose. ml h-1
CLIV Total clearance of drug following an IV dose. ml h-1
CLint Intrinsic metabolic clearance is defined as ratio of maximum metabolism rate, Vmax, and the Michaelis-Menten constant, Km. ml h-1 RT p165
CL12 Inter-compartment distribution between the central compartment and the peripheral compartment. ml h-1
CL ratio Ratio of the clearance (drug interaction parameter). Unit free
Cmax Highest drug concentration observed in plasma following administration of an extravascular dose. mg L-1 RT pxii
Cmax ratio The ratio of Cmax (drug interaction parameter). Unit free
Css Concentration of drug in plasma at steady state during a constant rate intravenous infusion. mg L-1 RT pxii
Css ratio The ratio of Css (drug interaction parameter). Unit free
E Extraction ratio is defined as the ratio between blood clearance, CLb, and the blood flow. Unit free RT p159
EH Hepatic extraction ratio. Unit free RT p161
F Bioavailability is defined as the proportion of the drug reaches the systemic blood. Unit free RT p42
FG Gut-wall bioavailability. Unit free
FH Hepatic bioavailability. Unit free RT p167
FR Renal bioavailability. Unit free RT p170
fe Fraction of drug systemically available that is excreted unchanged in urine. Unit free RT pxiii
fm Fraction of drug systemically available that is converted to a metabolite. Unit free RT pxiii
fu Ratio of unbound and total drug concentrations in plasma. Unit free RT pxiii
k Elimination rate constant. h-1 RT pxiii
K12, k21 Distribution rate constants between central compartment and peripheral compartment. h-1
ka Absorption rate constant. h-1 RT pxiii
ke Urinary excretion rate constant. h-1 RT pxiii
km Rate constant for the elimination of a metabolite. h-1 RT pxiii
Km Michaelis-Menten constant. mg L-1 RT pxiii
MRT Mean time a molecular resides in body. h RT pxiv
Q Blood flow. L h-1 RT pxiv
QH Hepatic blood flow. L h-1 RT pxiv
tmax Time at which the highest drug concentration occurs following administration of an extravascular dose. h RT pxiv
t1/2 Half-life of the drug disposition. h RT pxiv
t1/2 ratio Half-life ratio (drug interaction parameter). Unit free
t1/2,α Half-life of the fast phase drug disposition. h
t1/2,β Half-life of the slow phase drug disposition. h
V Volume of distribution based on drug concentration in plasma. L RT pxiv
Vb Volume of distribution based on drug concentration in blood. L RT pxiv
V1 Volume of distribution of the central compartment. L RT pxiv
V2 Volume of distribution of the peripheral compartment. L
Vss Volume of distribution under the steady state concentration. L RT pxiv
Vmax Maximum rate of metabolism by an enzymatically mediated reaction. mg h-1 RT pxiv
λ1, λ2 Disposition rate constants in a two-compartment model. h-1 GP p84
Pharmacokinetics Models Non-Compartment Use drug concentration measurements directly to estimate PK parameters, such as AUC, CL, Cmax, Tmax, t1/2, F, and V. GP p409
One Compartment Model It assumes the whole body is a homogeneous compartment, and the distribution of the drug from the blood to tissue is very fast. It assumes either a first order or a zero order absorption rate and a first order eliminate rate. Its PK parameters include (ka, V, CL, F). RT p34
GP p1
Two Compartment Model It assumes the whole body can be divided into two compartments: central compartment (i.e. systemic compartment) and peripheral compartment (i.e. tissue compartment). It assumes either a first order or a zero order absorption rate and a first order eliminate and distribution rates. Its PK parameters include (ka, V1, V2, CL, CL12, F). GP p84
Study Designs Hypothesis Bioequivalence, drug interaction, pharmacogenetics, and disease conditions.
Design Single arm or multiple arms; cross-over or fixed order design; with or without randomization; with or without stratification; prescreening or no-prescreening; prospective or retrospective studies; and case reports or cohort studies.
Sample size The number of subjects, and the number of plasma or urine samples per subject.
Time points Sampling time points and dosing time points.
Sample types Blood, plasma, and urine.
Dose Subject specific doses.
Quantification methods HPLC/UV, LC/MS/MS, LC/MS, radiographic

Rowland Malcolm and Tozer N. Thomas Clinical Pharmacokinetics Concepts and Applications, 3rd edition. 1995, Lippincott Williams & Wilkins.

Gibaldi Milo and Perrier Donald. Pharmacokinetics, 2nd edition. 1982, Dekker.

Wu et al.

Wu et al. BMC Bioinformatics 2013 14:35   doi:10.1186/1471-2105-14-35

Open Data