The differential equation is dC/dt = -Cl * C/V -Clp *(C-Cp)/V + 1/V * dD/dt, dCb/dt=Cl*C/Vb+Clb*(C-Cb)/Vp and E=E0+a*Cb^b/(Cbm^b+Cb^b)
where C is the concentration, Cl the total clearance (metabolic and excretion), V the distribution volume, Clb is the Clearance
to the biophase compartment, Vb is the volume of the biophase compartment, D the input dosing regime
E is the measured effect, E0 a baseline effect, a and b fitting constants and Cbm the biophase concentration at which
half the maximum effect is attained.