Peripheral Volume

Peripheral Volume, notated $V_{p e r i p h e r a l}$ , is the volume of the peripheral compartment in multi-compartment models. The peripheral compartment represents all tissues in the body outside the central circulatory system. The peripheral compartment should not be confused with peripheral blood, which is represented by the central compartment.

For large molecules, the peripheral volume is defined as the volume of the interstitial space that the drug can occupy within the body outside the central circulatory system. The volume of the peripheral compartment scales with body weight, notated $B W$ , according to the formula:

\frac{V_{p e r i p h e r a l, S p e c i e s 1}}{V_{p e r i p h e r a l, S p e c i e s 2}} = \frac{B W_{S p e c i e s 1}}{B W_{S p e c i e s 2}}

In ADCs, the peripheral volume is assumed to be the same for both conjugated antibody and the free payload.

Typical Values

Using this formula, the peripheral compartment volume can be scaled to the desired body weight using the literature-based values below. Note that compartmental volumes are considered to scale to body weight across different species.

Species	$V_{p e r i p h e r a l}$ (L)	$B W$ (kg)	Reference
Human	13	70	Shah and Betts 2012*
Cynomologus monkey	0.62	3.5	Hardiansyah and Ng 2018**
Rat	0.057	0.25	Shah and Betts 2012*
Mouse	0.0057	0.02	Shah and Betts 2012*

*The peripheral volume is considered to be the sum of peripheral tissue plasma and interstitial fluid volumes.

**Value listed in table is scaled by body weight from values reported for rhesus monkeys