Animal-to-human extrapolation of the pharmacokinetic and pharmacodynamic properties of buprenorphine.
OBJECTIVE
This investigation describes the interspecies scaling of the pharmacokinetics and pharmacodynamics of buprenorphine.


METHODS
Data on the time course of the antinociceptive and respiratory depressant effects of buprenorphine in rats and in humans were simultaneously analysed on the basis of a mechanism-based pharmacokinetic-pharmacodynamic model.


RESULTS
An allometric three-compartment pharmacokinetic model described the time course of the concentration in plasma. The value of the allometric coefficient for clearance was 35.2 mL/min (relative standard error [RSE] = 5.6%) and the value of the allometric exponent was 0.76 (RSE 5.61%). A combined biophase distribution-receptor association/dissociation model with a linear transduction function described hysteresis between plasma concentration and effect. The values of the drug-specific pharmacodynamic parameters were identical in rats and in humans. For the respiratory depressant effect, the values of the second-order rate constant of receptor association (k(on)) and the first-order rate constant of receptor dissociation (k(off)) were 0.23 mL/ng/min (RSE = 15.8%) and 0.014 min(-1) (RSE = 27.7%), respectively, and the value of the equilibrium dissociation constant (K(diss)) was 0.13 nmol/L. The value of the intrinsic activity alpha was 0.52 (RSE = 3.4%). For the antinociceptive effect, the values of the k(on) and k(off) were 0.015 mL/ng/min (RSE = 18.3%) and 0.053 min(-1) (RSE = 23.1%), respectively. The value of the K(diss) was 7.5 nmol/L. An allometric equation described the scaling of the system-specific parameter, the first-order distribution rate constant (k(e0)). The value of the allometric coefficient for the k(e0) was 0.0303 min(-1) (RSE = 11.3%) and the value of the exponent was -0.28 (RSE = 9.6%).


CONCLUSIONS
The different values of the drug-specific pharmacodynamic parameters are consistent with the different opioid mu receptor subtypes involved in the antinociceptive and respiratory depressant effects.
Yassen
Ashraf
A
Leiden/Amsterdam Center for Drug Research, Division of Pharmacology, Gorleaus Laboratories, Leiden, The Netherlands.
Olofsen
Erik
E
Kan
Jingmin
J
Dahan
Albert
A
Danhof
Meindert
M
D000701:Analgesics, Opioid / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D000818:Animals; D002047:Buprenorphine / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004333:Drug Administration Routes; D006801:Humans; D008954:Models, Biological; D051381:Rats; D015203:Reproducibility of Results; D012131:Respiratory Insufficiency / Q000139:chemically induced
D000701:Analgesics, Opioid; D002047:Buprenorphine