Discovery and Preclinical Characterization of BIIB129, a Covalent, Selective, and Brain-Penetrant BTK Inhibitor for the Treatment of Multiple Sclerosis.

Multiple sclerosis (MS) is a chronic disease with an underlying pathology characterized by inflammation-driven neuronal loss, axonal injury, and demyelination. Bruton's tyrosine kinase (BTK), a nonreceptor tyrosine kinase and member of the TEC family of kinases, is involved in the regulation, migration, and functional activation of B cells and myeloid cells in the periphery and the central nervous system (CNS), cell types which are deemed central to the pathology contributing to disease progression in MS patients. Herein, we describe the discovery of BIIB129 (25), a structurally distinct and brain-penetrant targeted covalent inhibitor (TCI) of BTK with an unprecedented binding mode responsible for its high kinome selectivity. BIIB129 (25) demonstrated efficacy in disease-relevant preclinical in vivo models of B cell proliferation in the CNS, exhibits a favorable safety profile suitable for clinical development as an immunomodulating therapy for MS, and has a low projected total human daily dose.

Discovery of Potent and Brain-Penetrant Tau Tubulin Kinase 1 (TTBK1) Inhibitors that Lower Tau Phosphorylation In Vivo.

Structural analysis of the known NIK inhibitor 3 bound to the kinase domain of TTBK1 led to the design and synthesis of a novel class of azaindazole TTBK1 inhibitors exemplified by 8 (cell IC50: 571 nM). Systematic optimization of this series of analogs led to the discovery of 31, a potent (cell IC50: 315 nM) and selective TTBK inhibitor with suitable CNS penetration (rat Kp,uu: 0.32) for in vivo proof of pharmacology studies. The ability of 31 to inhibit tau phosphorylation at the disease-relevant Ser 422 epitope was demonstrated in both a mouse hypothermia and a rat developmental model and provided evidence that modulation of this target may be relevant in the treatment of Alzheimer's disease and other tauopathies.

Developing pediatric three-dimensional upper airway normative values using fixed and interactive thresholds.

OBJECTIVE: To develop and compare pediatric upper airway three-dimensional normative values using the two most commonly used cone beam computed tomography (CBCT) software: Invivo5 (fixed threshold) and Dolphin 3D (interactive threshold). STUDY DESIGN: Out of 3738 CBCT scans, scans of 81 pediatric patients were utilized after applying strict exclusion criteria. The sample was grouped into two age groups (7-11 and 12-17 years). Intra-class correlation coefficient was used to test intra-rater and inter-rater reliability and showed coefficients greater than 0.9 indicating good reliability of the methods used. RESULTS: Paired t tests showed that volumetric and area measurements obtained using Dolphin 3D were significantly larger than those obtained using Invivo5 (p < 0.05). The mean minimal cross-sectional areas (MCSA) for Dolphin 3D were 151 mm2 and 177 mm2 for age groups 1 and 2, respectively. The mean MCSA values for Invivo5 for age groups 1 and 2 were 120 mm2 and 145 mm2, respectively. CONCLUSION: Pediatric upper airway volumetric, area, and linear measurements were reported after applying strict exclusion criteria including a validated sleep questionnaire. Our goal is that clinicians utilize the proposed-here normative values for screening and assist in the timely diagnosis and management of pediatric sleep apnea.

Computerized measurement of the location and value of the minimum sagittal linear dimension of the upper airway on reconstructed lateral cephalograms compared with 3-dimensional values.

INTRODUCTION: Identifying the location and value of the smallest airway dimension can be useful in screening and planning treatment for patients with obstructive sleep apnea. Our objectives in this study were to (1) objectively identify the vertical location and value of the minimum sagittal linear dimension (MSLD) on 2-dimensional reconstructed lateral cephalograms (RLCs), (2) compare the location and value of the MSLD on RLCs with the vertical location and sagittal dimension of the minimum cross-sectional area (MCSA), and (3) investigate the association between the MSLD on RLCs and both the MCSA and the airway volume. METHODS: Cone-beam computed tomography (CBCT) scans of 91 patients, in 3 age groups (<20, 20-40, and >40 years), were used to perform 3-dimensional assessments of the upper airway and reconstruct lateral cephalograms. Airway volume, MCSA, vertical level, and sagittal dimension of MCSA on the CBCT scans were obtained using Dolphin 3D software (version 11.7; Dolphin Imaging, Chatsworth, Calif). Customized software was used to objectively obtain the location and value of the MSLD of the airway on RLCs. RESULTS: In all age groups, correlation tests showed significant correlations between the MSLD on RLCs and both the MCSA (rs ≥0.59; P <0.001) and the airway volume (rs ≥0.37; P <0.05). Additionally, there were significant correlations between the vertical location of the MSLD and the vertical location of the MCSA (rs ≥0.41; P <0.05) and between the MSLD and the sagittal dimension of the MCSA (r ≥0.61; P <0.001). Bland-Altman plots for the MSLD and the sagittal dimension of the MCSA showed much narrower 95% limits of agreement compared with the Bland-Altman plots for the vertical locations of the MSLD and the MCSA. CONCLUSIONS: Two-dimensional images may be used as a screening tool and to identify the sagittal dimension of the smallest airway dimension. However, comprehensive assessment of airway characteristics is better achieved with CBCT-based 3-dimensional evaluation.

Potent PDZ-Domain PICK1 Inhibitors that Modulate Amyloid Beta-Mediated Synaptic Dysfunction.

Protein interacting with C kinase (PICK1) is a scaffolding protein that is present in dendritic spines and interacts with a wide array of proteins through its PDZ domain. The best understood function of PICK1 is regulation of trafficking of AMPA receptors at neuronal synapses via its specific interaction with the AMPA GluA2 subunit. Disrupting the PICK1-GluA2 interaction has been shown to alter synaptic plasticity, a molecular mechanism of learning and memory. Lack of potent, selective inhibitors of the PICK1 PDZ domain has hindered efforts at exploring the PICK1-GluA2 interaction as a therapeutic target for neurological diseases. Here, we report the discovery of PICK1 small molecule inhibitors using a structure-based drug design strategy. The inhibitors stabilized surface GluA2, reduced Aß-induced rise in intracellular calcium concentrations in cultured neurons, and blocked long term depression in brain slices. These findings demonstrate that it is possible to identify potent, selective PICK1-GluA2 inhibitors which may prove useful for treatment of neurodegenerative disorders.

Discovery of novel pyrazole-containing benzamides as potent RORγ inverse agonists.

The nuclear receptor RORγ plays a central role in controlling a pro-inflammatory gene expression program in several lymphocyte lineages including TH17 cells. RORγ-dependent inflammation has been implicated in the pathogenesis of several major autoimmune diseases and thus RORγ is an attractive target for therapeutic intervention in these diseases. Starting from a lead biaryl compound 4a, replacement of the head phenyl moiety with a substituted aminopyrazole group resulted in a series with improved physical properties. Further SAR exploration led to analogues (e.g., 4j and 5m) as potent RORγ inverse agonists.

N-terminally PEGylated human interferon-beta-1a with improved pharmacokinetic properties and in vivo efficacy in a melanoma angiogenesis model.

PEGylation of IFN-alpha has been used successfully to improve the pharmacokinetic properties and efficacy of the drug. To prepare a PEGylated form of human interferon-beta-1a (IFN-beta-1a) suitable for testing in vivo, we have synthesized 20 kDa mPEG-O-2-methylpropionaldehyde and used it to modify the N-terminal alpha-amino group of the cytokine. The PEGylated protein retained approximately 50% of the activity of the unmodified protein and had significantly improved pharmacokinetic properties following intravenous administration in rats. The clearance and volume of distribution at steady state were reduced approximately 30-fold and approximately 4-fold, respectively, resulting in a significant increase in systemic exposure as determined by the area under the curve. The elimination half-life of the PEGylated protein was approximately 13-fold greater than for the unmodified protein. The unmodified and PEGylated proteins were tested for their ability to inhibit the formation of radially oriented blood vessels entering the periphery of human SK-MEL-1 melanoma tumors in athymic nude homozygous (nu/nu) mice. In a single dose comparison study, administration of 1 x 10(6) units of unmodified IFN-beta-1a resulted in a 29% reduction in vessel number, while 1 x 10(6) units of PEGylated IFN-beta-1a resulted in a 58% reduction. Both treatments resulted in statistically significant reductions in mean vessel number as compared to the vehicle (control)-treated mice, with the PEGylated IFN-beta-1a-treated mice showing a statistically significantly greater reduction in mean vessel number as compared to the unmodified IFN-beta-1a-treated mice. In a multiple versus single dose comparison study, daily administration of 1 x 10(6) units of unmodified IFN-beta-1a for 9 days resulted in a 51% reduction in vessel number, while a single dose of 1 x 10(6) units of the PEGylated protein resulted in a 66% reduction. Both treatments resulted in statistically significant reductions in mean vessel number as compared to the vehicle-treated mice, with the PEGylated IFN-beta-1a-treated mice showing a statistically significantly greater reduction in mean vessel number as compared to the unmodified IFN-beta-1a-treated mice. Therefore, the improved pharmacokinetic properties of the modified protein translated into improved efficacy. Since unmodified IFN-beta is used for the treatment of multiple sclerosis and hepatitis C virus infection, a PEGylated form of the protein such as 20 kDa mPEG-O-2-methylpropionaldehyde-modified IFN-beta-1a may serve as a useful adjunct for the treatment of these diseases. In addition, the antiangiogenic effects of PEGylated IFN-beta-1a may be harnessed for the treatment of certain cancers, either as a sole agent or in combination with other antitumor drugs.