The utility of pharmacokinetic-pharmacodynamic modeling in the discovery and optimization of selective S1P(1) agonists.

Authors: Taylor S, Gray JR, Willis R, Deeks N, Haynes A, Campbell C, Gaskin P, Leavens K, Demont E, Dowell S, Cryan J, Morse M, Patel A, Garden H and Witherington J.
Publisher/Year: Xenobiotica 42(7):671-86.
Pub Med ID/Journal ID: PMID:22225501

Abstract

Sphingosine-1-phosphate (S1P(1)) receptor agonists such as Fingolimod (FTY-720) are a novel class of immunomodulators that have clinical utility in the treatment of remitting relapsing multiples sclerosis. This class of compound act by inducing peripheral lymphopenia. Using an integrated pharmacokinetic/pharmacodynamic (PK-PD) approach based on an in vivo rat model, novel S1P(1) agonists were identified with a predicted more rapid rate of reversibility of lymphocyte reduction in human compared to Fingolimod. The in vivo potency of 15 compounds based on PK-PD modelling of the rat lymphocyte reduction model was correlated with in vitro measures of potency at the S1P(1) receptor using β arrestin recruitment and G-protein signalling. A structurally novel S1P(1) agonist was identified and predictions of human pharmacokinetics and clinical dose are presented.