The discovery of N-cyclopropyl-4-methyl-3-[6-(4-methylpiperazin-1-yl)-4-oxoquinazolin-3(4H)-yl]benzamide (AZD6703), a clinical p38α MAP kinase inhibitor for the treatment of inflammatory diseases.

A novel, potent and selective quinazolinone series of inhibitors of p38α MAP kinase has been identified. Modifications designed to address the issues of poor aqueous solubility and high plasma protein binding as well as embedded aniline functionalities resulted in the identification of a clinical candidate N-cyclopropyl-4-methyl-3-[6-(4-methylpiperazin-1-yl)-4-oxoquinazolin-3(4H)-yl]benzamide (AZD6703). Optimisation was guided by understanding of the binding modes from X-ray crystallographic studies which showed a switch from DFG 'out' to DFG 'in' as the inhibitor size was reduced to improve overall properties.

Engineering a high-affinity anti-IL-15 antibody: crystal structure reveals an α-helix in VH CDR3 as key component of paratope.

Interleukin (IL) 15 is an inflammatory cytokine that plays an essential role in the activation, proliferation, and maintenance of specific natural killer cell and T-cell populations, and has been implicated as a mediator of inflammatory diseases. An anti-IL-15 antibody that blocked IL-15-dependent cellular responses was isolated by phage display and optimised via mutagenesis of the third complementarity-determining regions (CDRs) of variable heavy (VH) and variable light chains. Entire repertoires of improved variants were recombined with each other to explore the maximum potential sequence space.

Structure of IL-17A in complex with a potent, fully human neutralizing antibody.

IL-17A is a pro-inflammatory cytokine produced by the newly identified Th17 subset of T-cells. We have isolated a human monoclonal antibody to IL-17A (CAT-2200) that can potently neutralize the effects of recombinant and native human IL-17A. We determined the crystal structure of IL-17A in complex with the CAT-2200 Fab at 2.

Imidazoles: SAR and development of a potent class of cyclin-dependent kinase inhibitors.

An imidazole series of cyclin-dependent kinase (CDK) inhibitors has been developed. Protein inhibitor structure determination has provided an understanding of the emerging structure activity trends for the imidazole series. The introduction of a methyl sulfone at the aniline terminus led to a more orally bioavailable CDK inhibitor that was progressed into clinical development.

Crystal structures of human ADAMTS-1 reveal a conserved catalytic domain and a disintegrin-like domain with a fold homologous to cysteine-rich domains.

The ADAMTS (a disintegrin-like and metalloproteinase domain with thrombospondin type I motifs) family of proteases plays a role in pathological conditions including arthritis, cancer, thrombotic thrombocytopenic purpura and the Ehlers-Danlos type VIIC and Weill-Marchesani genetic syndromes. Here, we report the first crystal structures for a member of the ADAMTS family, ADAMTS-1. Originally cloned as an inflammation-associated gene, ADAMTS-1 has been shown to be involved in tissue remodelling, wound healing and angiogenesis.

Prevention of MKK6-dependent activation by binding to p38alpha MAP kinase.

Inhibition of p38alpha MAP kinase is a potential approach for the treatment of inflammatory disorders. MKK6-dependent phosphorylation on the activation loop of p38alpha increases its catalytic activity and affinity for ATP. An inhibitor, BIRB796, binds at a site used by the purine moiety of ATP and extends into a "selectivity pocket", which is not used by ATP.

SAR and inhibitor complex structure determination of a novel class of potent and specific Aurora kinase inhibitors.

A novel series of 5-aminopyrimidinyl quinazolines has been developed from anilino-quinazoline 1, which was identified in a high throughput screen for Aurora A. Introduction of the pyrimidine ring and optimisation of the substituents both on this ring and at the C7 position of the quinazoline led to the discovery of compounds that are highly specific Aurora kinase inhibitors. Co-crystallisation of one of these inhibitors with a fragment of Aurora A shows the importance of the benzamido group in achieving selectivity.

Imidazo[1,2-b]pyridazines: a potent and selective class of cyclin-dependent kinase inhibitors.

Modification of imidazo[1,2-a]pyridine CDK inhibitors lead to identification of less lipophilic imidazo[1,2-b]pyridazine series of CDK inhibitors. Although several equivalent compounds from these two series have similar structure and show similar CDK activity, the SAR of the two series differs significantly. Protein inhibitor structure determination has confirmed differences in binding mode and given some understanding of these differences in SAR.

Crystal structure of human thymidine phosphorylase in complex with a small molecule inhibitor.

Human thymidine phosphorylase (HTP), also known as platelet-derived endothelial cell growth factor (PD-ECGF), is overexpressed in certain solid tumors where it is linked to poor prognosis. HTP expression is utilized for certain chemotherapeutic strategies and is also thought to play a role in tumor angiogenesis. We determined the structure of HTP bound to the small molecule inhibitor 5-chloro-6-[1-(2-iminopyrrolidinyl) methyl] uracil hydrochloride (TPI).

Imidazo[1,2-a]pyridines: a potent and selective class of cyclin-dependent kinase inhibitors identified through structure-based hybridisation.

High-throughput screening identified the imidazo[1,2-a]pyridine and bisanilinopyrimidine series as inhibitors of the cyclin-dependent kinase CDK4. Comparison of their experimentally-determined binding modes and emerging structure-activity trends led to the development of potent and selective imidazo[1,2-a]pyridine inhibitors for CDK4 and in particular CDK2.

Cyclin-dependent kinase 4 inhibitors as a treatment for cancer. Part 2: identification and optimisation of substituted 2,4-bis anilino pyrimidines.

Through chemical modification and X-ray crystallography we identified the 2,4-bis anilino pyrimidines as potent inhibitors of CDK4. Herein, we describe the optimisation of this series.

Cyclin-dependent kinase 4 inhibitors as a treatment for cancer. Part 1: identification and optimisation of substituted 4,6-bis anilino pyrimidines.

Using a high-throughput screening campaign, we identified the 4,6-bis anilino pyrimidines as inhibitors of the cyclin-dependent kinase, CDK4. Herein we describe the further chemical modification and use of X-ray crystallography to develop potent and selective in vitro inhibitors of CDK4.

Crystal structure of human MMP9 in complex with a reverse hydroxamate inhibitor.

Matrix metalloproteinases (MMPs) and their inhibitors are important in connective tissue re-modelling in diseases of the cardiovascular system, such as atherosclerosis. Various members of the MMP family have been shown to be expressed in atherosclerotic lesions, but MMP9 is consistently seen in inflammatory atherosclerotic lesions. MMP9 over-expression is implicated in the vascular re-modelling events preceding plaque rupture (the most common cause of acute myocardial infarction).