Abstract |
Bruton's tyrosine kinase (BTK) plays a critical role in the development, differentiation, and proliferation of B-lineage cells, making it an attractive target for the treatment of rheumatoid arthritis. The objective of this study was to evaluate the antiarthritis effect of GDC-0834 [R-N-(3-(6-(4-(1,4-dimethyl-3-oxopiperazin-2-yl)phenylamino)-4-methyl-5-oxo-4,5-dihydropyrazin-2-yl)-2-methylphenyl)-4,5,6,7-tetrahydrobenzo[b] thiophene-2-carboxamide], a potent and selective BTK inhibitor, and characterize the relationship between inhibition of BTK phosphorylation (pBTK) and efficacy. GDC-0834 inhibited BTK with an in vitro IC(50) of 5.9 and 6.4 nM in biochemical and cellular assays, respectively, and in vivo IC(50) of 1.1 and 5.6 μM in mouse and rat, respectively. Administration of GDC-0834 (30-100 mg/kg) in a rat collagen-induced arthritis (CIA) model resulted in a dose-dependent decrease of ankle swelling and reduction of morphologic pathology. An integrated disease progression pharmacokinetic/pharmacodynamic model where efficacy is driven by pBTK inhibition was fit to ankle-diameter time-course data. This model incorporated a transit model to characterize nondrug-related decreases in ankle swelling occurring at later stages of disease progression in CIA rats. The time course of ankle swelling in vehicle animals was described well by the base model. Simultaneous fitting of data from vehicle- and GDC-0834-treated groups showed that overall 73% inhibition of pBTK was needed to decrease the rate constant describing the ankle swelling increase (k(in)) by half. These findings suggest a high degree of pBTK inhibition is required for maximal activity of the pathway on inflammatory arthritis in rats.
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Authors | Lichuan Liu, Julie Di Paolo, Jim Barbosa, Hong Rong, Karin Reif, Harvey Wong |
Journal | The Journal of pharmacology and experimental therapeutics
(J Pharmacol Exp Ther)
Vol. 338
Issue 1
Pg. 154-63
(Jul 2011)
ISSN: 1521-0103 [Electronic] United States |
PMID | 21521773
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- Antirheumatic Agents
- N-(3-(6-(4-(1,4-dimethyl-3-oxopiperazin-2-yl)phenylamino)-4-methyl-5-oxo-4,5-dihydropyrazin-2-yl)-2-methylphenyl)-4,5,6,7-tetrahydrobenzo(b)thiophene-2-carboxamide
- Protein Kinase Inhibitors
- Pyrimidinones
- Thiophenes
- Protein-Tyrosine Kinases
- Agammaglobulinaemia Tyrosine Kinase
- Btk protein, mouse
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Topics |
- Agammaglobulinaemia Tyrosine Kinase
- Animals
- Antirheumatic Agents
(chemistry, pharmacology, therapeutic use)
- Arthritis, Experimental
(drug therapy, enzymology)
- Cattle
- Female
- Male
- Mice
- Mice, Inbred BALB C
- Models, Chemical
- Phosphorylation
(drug effects, physiology)
- Protein Kinase Inhibitors
(chemistry, pharmacology, therapeutic use)
- Protein-Tyrosine Kinases
(antagonists & inhibitors, metabolism)
- Pyrimidinones
(chemistry, pharmacology, therapeutic use)
- Rats
- Rats, Inbred Lew
- Rats, Sprague-Dawley
- Thiophenes
(chemistry, pharmacology, therapeutic use)
- Treatment Outcome
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