Discovery of GSK1070916, a potent and selective inhibitor of Aurora B/C kinase.

The Aurora kinases play critical roles in the regulation of mitosis and are frequently overexpressed or amplified in human tumors. Selective inhibitors may provide a new therapy for the treatment of tumors with Aurora kinase amplification. Herein we describe our lead optimization efforts within a 7-azaindole-based series culminating in the identification of GSK1070916 (17k). Key to the advancement of the series was the introduction of a 2-aryl group containing a basic amine onto the azaindole leading to significantly improved cellular activity. Compound 17k is a potent and selective ATP-competitive inhibitor of Aurora B and C with K(i)* values of 0.38 +/- 0.29 and 1.5 +/- 0.4 nM, respectively, and is >250-fold selective over Aurora A. Biochemical characterization revealed that compound 17k has an extremely slow dissociation half-life from Aurora B (>480 min), distinguishing it from clinical compounds 1 and 2. In vitro treatment of A549 human lung cancer cells with compound 17k results in a potent antiproliferative effect (EC(50) = 7 nM). Intraperitoneal administration of 17k in mice bearing human tumor xenografts leads to inhibition of histone H3 phosphorylation at serine 10 in human colon cancer (Colo205) and tumor regression in human leukemia (HL-60). Compound 17k is being progressed to human clinical trials.

The validity and responsiveness of three quality of life measures in the assessment of psoriasis patients: results of a phase II study.

BACKGROUND: Patient-reported outcome (PROs) measures are being used more frequently in investigational studies of treatments for moderate to severe plaque psoriasis. The objective of this study was to examine the relationships among the Dermatology Life Quality Index (DLQI), the Short Form 36 (SF-36), and the EuroQOL 5D (EQ-5D) and to assess their validity, responsiveness, and estimates of minimum important differences. METHODS: A Phase II, randomized, double-blind, parallel group, placebo-controlled, multi-center clinical trial assessed the clinical efficacy and safety of two doses of subcutaneously administered adalimumab vs. placebo for 12 weeks in the treatment of 147 patients with moderate to severe plaque psoriasis. This study provided the opportunity to evaluate the validity and responsiveness to change in clinical status of PROs instruments. Patients completed the DLQI, SF-36, and EQ-5D questionnaires at baseline and at 12 weeks. Blinded investigators assessed the Psoriasis Area and Severity Index (PASI) scores and the Physician's Global Assessment (PGA) scores of enrolled patients. The responsiveness of the measures to changes in the clinical endpoints from baseline to Week 12 was assessed. Estimates of minimum important differences (MID) were derived. All analyses were performed with blinded data; findings and conclusions were not biased based on treatment condition. RESULTS: The dermatology-specific DLQI was highly correlated to clinical endpoints at baseline and at Week 12, and was the most responsive PRO to changes in endpoints. Compared with the SF-36, the EQ-5D index score and VAS scores were generally more highly correlated with clinical endpoints, but displayed about the same degree of responsiveness. The most responsive SF-36 scales were the Bodily Pain and Social Functioning scales. Estimates of the MID for the DLQI ranged from 2.3-5.7 and for the SF-36 Physical Component Summary (PCS) score ranged from 2.5-3.9. CONCLUSION: This study provides support for the continued use of the DLQI and SF-36 PCS in the assessment of treatments for psoriasis. On the basis of the results from this trial, the EQ-5D should be considered as a general PRO measure in future clinical trials of patients with moderate to severe plaque psoriasis.

Optimization of alpha-acylaminoketone ecdysone agonists for control of gene expression.

Fifteen new alpha-acylaminoketones were prepared by four different routes in an initial effort to optimize the potency of these compounds as ecdysone agonists. The compounds were assayed in mammalian cells expressing the ecdysone receptors from Bombyx mori (BmEcR) and Choristoneura fumiferana (CfEcR) for their ability to cause expression of a reporter gene downstream of an ecdysone response element. A new alpha-acylaminoketone was identified which had activity equal to that of the standard dibenzoylhydrazine ecdysone agonist GS()-E in the assay based on CfEcR.

Synthesis and SAR of cis-1-benzoyl-1,2,3,4-tetrahydroquinoline ligands for control of gene expression in ecdysone responsive systems.

A library of 35 cis-1-benzoyl-2-methyl-4-(phenylamino)-1,2,3,4-tetrahydroquinolines was prepared. The compounds bore various substitutuents on the benzoyl ring, at the 4-position of the phenylamino ring and at the 6-position of the tetrahydroquinoline ring. The compounds were assayed for their ability to cause expression of a reporter gene downstream of an ecdysone response element in a mammalian cell line engineered to express the ecdysone receptor from Aedes aegypti. In general, compounds with small lipophilic substituents at the meta and para-positions of the benzoyl ring and hydrogen or fluorine at the 4-position of the phenylamino ring and the 6-position of the tetrahydroquinoline ring were the most potent.

Synthesis and SAR of alpha-acylaminoketone ligands for control of gene expression.

A lead discovery library and a follow-up focused library of alpha-acylaminoketones were designed based on known dibenzoylhydrazine ecdysone agonists, including GS(TM)-E. The compounds were assayed in mammalian cells expressing the ecdysone receptor from Bombyx mori for their ability to cause expression of a reporter gene downstream of an ecdysone response element. The most potent alpha-acylaminoketones were comparable to GS(TM)-E in this assay.