An anti-TNF-glucocorticoid receptor modulator antibody-drug conjugate is efficacious against immune-mediated inflammatory diseases.

Glucocorticoids (GCs) are efficacious drugs used for treating many inflammatory diseases, but the dose and duration of administration are limited because of severe side effects. We therefore sought to identify an approach to selectively target GCs to inflamed tissue. Previous work identified that anti-tumor necrosis factor (TNF) antibodies that bind to transmembrane TNF undergo internalization; therefore, an anti-TNF antibody-drug conjugate (ADC) would be mechanistically similar, where lysosomal catabolism could release a GC receptor modulator (GRM) payload to dampen immune cell activity. Consequently, we have generated an anti-TNF-GRM ADC with the aim of inhibiting pro-inflammatory cytokine production from stimulated human immune cells. In an acute mouse model of contact hypersensitivity, a murine surrogate anti-TNF-GRM ADC inhibited inflammatory responses with minimal effect on systemic GC biomarkers. In addition, in a mouse model of collagen-induced arthritis, single-dose administration of the ADC, delivered at disease onset, was able to completely inhibit arthritis for greater than 30 days, whereas an anti-TNF monoclonal antibody only partially inhibited disease. ADC treatment at the peak of disease was also able to attenuate the arthritic phenotype. Clinical data for a human anti-TNF-GRM ADC (ABBV-3373) from a single ascending dose phase 1 study in healthy volunteers demonstrated antibody-like pharmacokinetic profiles and a lack of impact on serum cortisol concentrations at predicted therapeutic doses. These data suggest that an anti-TNF-GRM ADC may provide improved efficacy beyond anti-TNF alone in immune mediated diseases while minimizing systemic side effects associated with standard GC treatment.

Design and Development of Glucocorticoid Receptor Modulators as Immunology Antibody-Drug Conjugate Payloads.

Glucocorticoid receptor modulators (GRM) are the first-line treatment for many immune diseases, but unwanted side effects restrict chronic dosing. However, targeted delivery of a GRM payload via an immunology antibody-drug conjugate (iADC) may deliver significant efficacy at doses that do not lead to unwanted side effects. We initiated our α-TNF-GRM ADC project focusing on identifying the optimal payload and a linker that afforded stable attachment to both the payload and antibody, resulting in the identification of the synthetically accessible maleimide-Gly-Ala-Ala linker. DAR 4 purified ADCs were shown to be more efficacious in a mouse contact hypersensitivity model than the parent α-TNF antibody. Analysis of P1NP and corticosterone biomarkers showed there was a sufficient therapeutic window between efficacy and unwanted effects. In a chronic mouse arthritis model, α-TNF-GRM ADCs were more efficacious than both the parent α-TNF mAb and an isotype control bearing the same GRM payload.

Development of Orally Efficacious Allosteric Inhibitors of TNFα via Fragment-Based Drug Design.

Tumor necrosis factor α (TNFα) is a soluble cytokine that is directly involved in systemic inflammation through the regulation of the intracellular NF-κB and MAPK signaling pathways. The development of biologic drugs that inhibit TNFα has led to improved clinical outcomes for patients with rheumatoid arthritis and other chronic autoimmune diseases; however, TNFα has proven to be difficult to drug with small molecules. Herein, we present a two-phase, fragment-based drug discovery (FBDD) effort in which we first identified isoquinoline fragments that disrupt TNFα ligand-receptor binding through an allosteric desymmetrization mechanism as observed in high-resolution crystal structures. The second phase of discovery focused on the de novo design and optimization of fragments with improved binding efficiency and drug-like properties. The 3-indolinone-based lead presented here displays oral, in vivo efficacy in a mouse glucose-6-phosphate isomerase (GPI)-induced paw swelling model comparable to that seen with a TNFα antibody.

S1P(1) receptor agonists: Assessment of selectivity and current clinical activity.

Interest in sphingosine-1-phosphate (S1P)(1) receptor agonists has increased steadily since the discovery that the mechanism of action of fingolimod (FTY-720)-induced lymphopenia is linked to the S1P GPCR family. Fingolimod is an agonist at four out of the five S1P family receptors. Adoptive cell transfer experiments and selective S1P(1) receptor agonists provided evidence that the S1P(1) receptor is the main target responsible for trapping lymphocytes in secondary lymphoid tissue. This readily accessible, translatable biomarker has been correlated with efficacy in rodent models of immune disease. Novartis AG filed for regulatory approval for fingolimod in the US and EU for the treatment of multiple sclerosis in December 2009. In addition, more selective compounds targeting S1P receptors from several companies have entered clinical trials. These compounds can be categorized into two classes of S1P(1) receptor agonists: amino alcohol prodrugs and second-generation direct agonists. This review focuses on the development of these compounds and the role of S1P receptor family selectivity.

Eleven amino acid glucagon-like peptide-1 receptor agonists with antidiabetic activity.

Glucagon-like peptide 1 (GLP-1) is a 30 or 31 amino acid peptide hormone that contributes to the physiological regulation of glucose homeostasis and food intake. Herein, we report the discovery of a novel class of 11 amino acid GLP-1 receptor agonists. These peptides consist of a structurally optimized 9-mer, which is closely related to the N-terminal 9 amino acids of GLP-1, linked to a substituted C-terminal biphenylalanine (BIP) dipeptide. SAR studies resulted in 11-mer GLP-1R agonists with similar in vitro potency to the native 30-mer. Peptides 21 and 22 acutely reduced plasma glucose excursions and increased plasma insulin concentrations in a mouse model of diabetes. These peptides also showed sustained exposures over several hours in mouse and dog models. The described 11-mer GLP-1 receptor agonists represent a new tool in further understanding GLP-1 receptor pharmacology that may lead to novel antidiabetic agents.

Scalable synthesis and isolation of the four stereoisomers of methyl 1-amino-3-(4-bromophenyl)cyclopentanecarboxylate, useful intermediates for the synthesis of S1P1 receptor agonists.

The individual isomers of methyl 1-amino-3-(4-bromophenyl)cyclopentanecarboxylate are useful intermediates for the synthesis of S1P1 receptor agonists. Herein we describe a scalable synthesis and isolation of each of the four stereoisomers of this compound in gram quantities with >98% ee and de. The utility of this approach is demonstrated by the synthesis of ((1R,3R)-1-amino-3-(4-octylphenyl)cyclopentyl)methanol in 7 steps, 11% overall yield, and >98% ee and de.

Discovery and optimization of (R)-prolinol-derived agonists of the Growth Hormone Secretagogue receptor (GHSR).

The discovery and optimization of a novel series of prolinol-derived GHSR agonists is described. This series emerged from a 11,520-member solid-phase library targeting the GPCR protein superfamily, and the rapid optimization of low micromolar hits into single-digit nanomolar leads can be attributed to the solid-phase synthesis of matrix libraries, which revealed multiple non-additive structure-activity relationships. In addition, the separation of potent diastereomers highlighted the influence of the alpha-methyl stereochemistry of the phenoxyacetamide sidechain on GHSR activity.

A distinct pattern of myofascial findings in patients after whiplash injury.

OBJECTIVE: To identify objective clinical examinations for the diagnosis of whiplash syndrome, whereby we focused on trigger points. DESIGN: A cross-sectional study with 1 measurement point. SETTING: A quiet treatment room in a rehabilitation center. PARTICIPANTS: Patients (n=124) and healthy subjects (n=24) participated in this study. Among the patient group were patients with whiplash-associated disorders (n=47), fibromyalgia (n=21), nontraumatic chronic cervical syndrome (n=17), and endogenous depression (n=15). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Each patient and control subject had a manual examination for trigger points of the semispinalis capitis, trapezius pars descendens, levator scapulae, scalenus medius, sternocleidomastoideus, and masseter muscles bilaterally. RESULTS: Forty (85.1%) of the patients with whiplash had positive trigger points in the semispinalis capitis muscle. The patients with whiplash had a significantly higher prevalence of positive trigger points in the semispinalis capitis muscle than any of the control groups (P<.05). For the other examined muscles, the prevalence of trigger points in the patients with whiplash did not differ significantly from the patients with fibromyalgia or nontraumatic chronic cervical syndrome. It did differ from the patients with endogenous depression and the healthy controls. CONCLUSIONS: Patients with whiplash showed a distinct pattern of trigger point distribution that differed significantly from other patient groups and healthy subjects. The semispinalis capitis muscle was more frequently affected by trigger points in patients with whiplash, whereas other neck and shoulder muscles and the masseter muscle did not differentiate between patients with whiplash and patients with nontraumatic chronic cervical syndrome or fibromyalgia.

Lead identification of 2-iminobenzimidazole antagonists of the chemokine receptor CXCR3.

Modification of a 2-iminobenzimidazole series derived from an HTS hit resulted in compounds with improved in-vitro species selectivity. Incorporation of an 8-quinoline amide and conformational rigidification of an aliphatic tether furnished potent compounds suitable for further lead optimization.

Discovery of small molecule benzimidazole antagonists of the chemokine receptor CXCR3.

High-throughput screening identified a low molecular weight antagonist of CXCR3 displaying micromolar activity in a membrane filtration-binding assay. Systematic modification of the benzimidazole core and tethered acetophenone moiety established tractable SAR of analogs with improved physicochemical properties and sub-micromolar activity across both human and murine receptors.

Potent and selective biphenyl azole inhibitors of adipocyte fatty acid binding protein (aFABP).

Herein we report the first disclosure of biphenyl azoles that are nanomolar binders of adipocyte fatty acid binding protein (aFABP or aP2) with up to thousand-fold selectivity against muscle fatty acid binding protein and epidermal fatty acid binding protein. In addition a new radio-ligand to determine binding against the three fatty acid binding proteins was also synthesized.

Tetrahydroisoquinoline 1-carboxamides as growth hormone secretagogues.

Several novel series of tetrahydroisoquinoline 1-carboxamides were prepared and shown to be potent growth hormone (GH) secretagogues. Among them, carbamate 12a-E2 displays excellent in vivo activity by increasing plasma GH 10-fold in an anesthetized IV rat model.

Correlation of high-throughput pregnane X receptor (PXR) transactivation and binding assays.

Pregnane X receptor (PXR) transactivation and binding assays have been developed into high-throughput assays, which are robust and reproducible (Z' > 0.5). For most compounds, there was a good correlation between the results of the transactivation and binding assays. EC(50) values of compounds in the transactivation assay correlated reasonably well with their IC(50) values in the binding assay. However, there were discrepancies with some compounds showing high binding affinity in the binding assay translated into low transactivation. The most likely cause for these discrepancies was an agonist-dependent relationship between binding affinity and transactivation response. In general, compounds that bound to human PXR and transactivated PXR tended to be large hydrophobic molecules.

Discovery of a potent and novel motilin agonist.

A novel series of dihydro- and tetrahydrotriazolopyridazine-1,3-dione-based amino acid derivatives were identified as very potent motilin receptor agonists. Incorporating one additional phenylethyl glycinamide subunit to 1 (EC(50) = 660 nM) was found to improve in vitro potency approximately 3000-fold, resulting in compound 10 (EC(50) = 0.22 nM). The more potent enantiomer 11A has an EC(50) of 0.047 nM in the motilin receptor functional assay and a K(i) of 0.7 nM in the binding assay. In addition, compound 11A was shown to have a significantly reduced tendency to cause receptor desensitization as compared with the motilin receptor agonist ABT-229.