Biologic-like In Vivo Efficacy with Small Molecule Inhibitors of TNFα Identified Using Scaffold Hopping and Structure-Based Drug Design Approaches.

Scaffold hopping and structure-based drug design were employed to identify substituted 4-aminoquinolines and 4-aminonaphthyridines as potent, small molecule inhibitors of tumor necrosis factor alpha (TNFα). Structure-activity relationships in both the quinoline and naphthyridine series leading to the identification of compound with excellent potency and pharmacokinetic profile are discussed. X-ray co-crystal structure analysis and ultracentrifugation experiments clearly demonstrate that these inhibitors distort the TNFα trimer upon binding, leading to aberrant signaling when the trimer binds to TNF receptor 1 (TNFR1).

Periodic, partial inhibition of IkappaB Kinase beta-mediated signaling yields therapeutic benefit in preclinical models of rheumatoid arthritis.

We have previously shown that inhibitors of IkappaB kinase beta (IKKbeta), including 4(2'-aminoethyl)amino-1,8-dimethylimidazo(1,2-a)quinoxaline (BMS-345541), are efficacious against experimental arthritis in rodents. In our efforts to identify an analog as a clinical candidate for the treatment of autoimmune and inflammatory disorders, we have discovered the potent and highly selective IKKbeta inhibitor 2-methoxy-N-((6-(1-methyl-4-(methylamino)-1,6-dihydroimidazo[4,5-d]pyrrolo[2,3-b]pyridin-7-yl)pyridin-2-yl)methyl)acetamide (BMS-066). Investigations of its pharmacology in rodent models of experimental arthritis showed that BMS-066 at doses of 5 and 10 mg/kg once daily was effective at protecting rats against adjuvant-induced arthritis, despite showing only weak inhibition at 10 mg/kg against a pharmacodymanic model of tumor necrosis factor alpha production in rats challenged with lipopolysaccharide.

Synthesis and biological evaluation of 4-amino derivatives of benzimidazoquinoxaline, benzimidazoquinoline, and benzopyrazoloquinazoline as potent IKK inhibitors.

We have recently identified BMS-345541 (1) as a highly selective and potent inhibitor of IKK-2 (IC50 = 0.30 microM), which however was considerably less potent against IKK-1 (IC50 = 4.0 microM).

Collagen and aggrecan degradation is blocked in interleukin-1-treated cartilage explants by an inhibitor of IkappaB kinase through suppression of metalloproteinase expression.

It has previously been shown that BMS-345541 [4(2'-aminoethyl)amino-1,8-dimethylimidazo(1,2-a)quinoxaline], a highly-selective inhibitor of IkappaB kinase (IKK), blocks both inflammation and joint destruction in murine collagen-induced arthritis. Although this agent has been shown to inhibit nuclear factor-kappaB-dependent cytokine expression in mice, we examined whether the inhibitor directly inhibits cytokine-driven metalloproteinase expression and cartilage degradation. In SW-1353 human chondrosarcoma cells, BMS-345541 inhibited interleukin-1 (IL-1)-dependent expression of matrix metalloproteinase (MMP)-1, MMP-3, and MMP-13 in a concentration-dependent manner.

BMS-345541 is a highly selective inhibitor of I kappa B kinase that binds at an allosteric site of the enzyme and blocks NF-kappa B-dependent transcription in mice.

The signal-inducible phosphorylation of serines 32 and 36 of I kappa B alpha is critical in regulating the subsequent ubiquitination and proteolysis of I kappa B alpha, which then releases NF-kappa B to promote gene transcription. The multisubunit I kappa B kinase responsible for this phosphorylation contains two catalytic subunits, termed I kappa B kinase (IKK)-1 and IKK-2. BMS-345541 (4(2'-aminoethyl)amino-1,8-dimethylimidazo(1,2-a)quinoxaline) was identified as a selective inhibitor of the catalytic subunits of IKK (IKK-2 IC(50) = 0.