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Author Contributions
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The manuscript was written through contributions of all authors.
All authors have given approval to the final version of the manu-
script.
ACKNOWLEDGMENT
We thank Dr. Eric Meade for his help editing the manuscript, Dr.
Hong Mei for helpful discussion, the MS and NMR groups for
spectroscopic data, and Drs. William Greenlee and Joseph Vacca
for support of the program.
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ABBREVIATIONS
CRTh2, chemoattractant receptor homologous molecule ex-
pressed on T-Helper type 2; SBDD, structure based drug design;
ICS, inhaled corticosteroids; SABAs, short-acting beta agonists;
LABAs, long-acting beta agonists; LAMAs, long-acting musca-
rinic antagonists; FDCs, fixed-dose combinations; DP2, Prosta-
glandin D2 receptor 2; TP receptor, thromboxane A2-prostanoid
receptor; PGD2, prostaglandin D2; MRL, Merck Research Labor-
atory; cAMP, cyclic adenosine monophosphate; SAR, structure-
activity relationship; PK, pharmacokinetics; AUC, area under
curve; TDI, time-dependent inhibition; PXR, pregnane X recep-
tor; LAR, late airway response; AHR, airway hyperresponsive-
ness; TFA, trifluoroacetic acid.
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