A long-acting factor VIII (FVIII) as a replacement therapy for hemophilia A would significantly improve treatment options for patients with hemophilia A. To develop a FVIII with an extended circulating half-life, but without a reduction in activity, we have engineered 23 FVIII variants with introduced surface-exposed cysteines to which a polyethylene glycol (PEG) polymer was specifically conjugated. Screening of variant expression level, PEGylation yield, and functional assay identified several conjugates retaining full in vitro coagulation activity and von Willebrand factor (VWF) binding. PEGylated FVIII variants exhibited improved pharmacokinetics in hemophilic mice and rabbits. In addition, pharmacokinetic studies in VWF knockout mice indicated that larger molecular weight PEG may substitute for VWF in protecting PEGylated FVIII from clearance in vivo. In bleeding models of hemophilic mice, PEGylated FVIII not only exhibited prolonged efficacy that is consistent with the improved pharmacokinetics but also showed efficacy in stopping acute bleeds comparable with that of unmodified rFVIII. In summary site-specifically PEGylated FVIII has the potential to be a long-acting prophylactic treatment while being fully efficacious for on-demand treatment for patients with hemophilia A. (Blood. 2010;116(2):270-279)

The CC chemokine receptor-1 (CCR1) is a prime therapeutic target for treating autoimmune diseases. Through high capacity screening followed by chemical optimization, we identified a novel non-peptide CCR1 antagonist, R-N-[5-chloro-2-[2-[4-[(4-fluorophenyl)methyl]-2-methyl-1-piperazinyl]-2-oxoethoxy]phenyl]urea hydrochloric acid salt (BX 471). Competition binding studies revealed that BX 471 was able to displace the CCR1 ligands macrophage inflammatory protein-1␣ (MIP-1␣), RANTES, and monocyte chemotactic protein-3 (MCP-3) with high affinity (K i ranged from 1 nM to 5.5 nM). BX 471 was a potent functional antagonist based on its ability to inhibit a number of CCR1-mediated effects including Ca 2؉ mobilization, increase in extracellular acidification rate, CD11b expression, and leukocyte migration. BX 471 demonstrated a greater than 10,000-fold selectivity for CCR1 compared with 28 G-protein-coupled receptors. Pharmacokinetic studies demonstrated that BX 471 was orally active with a bioavailability of 60% in dogs. Furthermore, BX 471 effectively reduces disease in a rat experimental allergic encephalomyelitis model of multiple sclerosis. This study is the first to demonstrate that a non-peptide chemokine receptor antagonist is efficacious in an animal model of an autoimmune disease. In summary, we have identified a potent, selective, and orally available CCR1 antagonist that may be useful in the treatment of chronic inflammatory diseases.It is clear that the inappropriate interaction of immune cells, such as T lymphocytes and monocytes, can lead to extensive inflammation and tissue destruction, which is a hallmark of several autoimmune diseases such as rheumatoid arthritis and multiple sclerosis. Immune cells are sent on their destructive journey by chemoattractant molecules known as chemokines, which interact with and signal through specific cell surface chemokine receptors. Chemokine receptors belong to the GPCR 1 superfamily and have been viewed as attractive therapeutic targets by the pharmaceutical industry mainly because of their central role in regulating leukocyte trafficking. The premise that drugs that can inhibit the directed migration and activation of immune cells could be useful therapeutically has prompted the search for specific and highly potent chemokine receptor antagonists.Autoimmune diseases like multiple sclerosis and rheumatoid arthritis are characterized by interactions between invading T lymphocytes and tissue macrophages that result in extensive inflammation, tissue damage, and chronic disease pathologies. Numerous studies have demonstrated CCR1 expression in these cell types, and a variety of evidence provides strong in vivo concept validation for a role of this receptor in animal models of these diseases. For example, Karpus et al. (1, 2) were able to show in a mouse EAE model of multiple sclerosis that antibodies to MIP-1␣ prevented the development of both initial and relapsing paralytic disease as well as infiltration of mononuclear cells into the central nervous system. Treatment wit...

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1 Lipoxins (LX) and aspirin-triggered 15-epi-lipoxins (ATL) exert potent anti-inflammatory actions. In the present study, we determined the anti-inflammatory efficacy of endogenous LXA 4 and LXB 4 , the stable ATL analog ATLa2, and a series of novel 3-oxa-ATL analogs (ZK-996, ZK-990, ZK-994, and ZK-142) after intravenous, oral, and topical administration in mice. 2 LXA 4 , LXB 4 , ATLa2, and ZK-994 were orally active, exhibiting potent systemic inhibition of zymosan A-induced peritonitis at very low doses (50 ng kg À1-50 mg kg À1 ). 3 Intravenous ZK-994 and ZK-142 (500 mg kg À1) potently attenuated hind limb ischemia/ reperfusion-induced lung injury, with 32712 and 5375% inhibition (Po0.05), respectively, of neutrophil accumulation in lungs. The same dose of ATLa2 had no significant protective action. 4 Topical application of ATLa2, ZK-994, and ZK-142 (B20 mg cm À2) prevented vascular leakage and neutrophil infiltration in LTB 4 /PGE 2 -stimulated ear skin inflammation. While ATLa2 and ZK-142 displayed approximately equal anti-inflammatory efficacy in this model, ZK-994 displayed a slower onset of action. 5 In summary, native LXA 4 and LXB 4 , and analogs ATLa2, ZK-142, and ZK-994 retain broad antiinflammatory effects after intravenous, oral, and topical administration. The 3-oxa-ATL analogs, which have enhanced metabolic and chemical stability and a superior pharmacokinetic profile, provide new opportunities to explore the actions and therapeutic potential for LX and ATL.

Background-Angiotensin II (Ang II) accelerates atherosclerosis and induces abdominal aortic aneurysm (AAA) in an experimental mouse model. Agonism of a G protein-coupled receptor by Ang II activates Rho-kinase and other signaling pathways and results in activation of proteolysis and apoptosis. Enhanced proteolysis and smooth muscle cell apoptosis are important mechanisms associated with AAA. In this study, we tested the hypothesis that fasudil, a Rho-kinase inhibitor, could attenuate Ang II-induced AAA formation by inhibiting vascular wall apoptosis and extracellular matrix proteolysis. Methods and Results-Six-month-old apolipoprotein E-deficient mice were infused with Ang II (1.44 mg · kg Ϫ1 · d