SAR and characterization of non-substrate isoindoline urea inhibitors of nicotinamide phosphoribosyltransferase (NAMPT).

Herein we disclose SAR studies that led to a series of isoindoline ureas which we recently reported were first-in-class, non-substrate nicotinamide phosphoribosyltransferase (NAMPT) inhibitors. Modification of the isoindoline and/or the terminal functionality of screening hit 5 provided inhibitors such as 52 and 58 with nanomolar antiproliferative activity and preclinical pharmacokinetics properties which enabled potent antitumor activity when dosed orally in mouse xenograft models. X-ray crystal structures of two inhibitors bound in the NAMPT active-site are discussed.

Thienopyridine ureas as dual inhibitors of the VEGF and Aurora kinase families.

In an effort to identify multi-targeted kinase inhibitors with a novel spectrum of kinase activity, a screen of Abbott proprietary KDR inhibitors against a broad panel of kinases was conducted and revealed a series of thienopyridine ureas with promising activity against the Aurora kinases. Modification of the diphenyl urea and C7 moiety of these compounds provided potent inhibitors with good pharmacokinetic profiles that were efficacious in mouse tumor models after oral dosing. Compound 2 (ABT-348) of this series is currently undergoing Phase I clinical trials in solid and hematological cancer populations.

Pyrazole diaminopyrimidines as dual inhibitors of KDR and Aurora B kinases.

In an effort to identify kinase inhibitors with dual KDR/Aurora B activity and improved aqueous solubility compared to the Abbott dual inhibitor ABT-348, a series of novel pyrazole pyrimidines structurally related to kinase inhibitor AS703569 were prepared. SAR work provided analogs with significant cellular activity, measureable aqueous solubility and moderate antitumor activity in a mouse tumor model after weekly ip dosing. Unfortunately these compounds were pan-kinase inhibitors that suffered from narrow therapeutic indices which prohibited their use as antitumor agents.

Regional anesthesia as compared with general anesthesia for surgery in geriatric patients with hip fracture: does it decrease morbidity, mortality, and health care costs? Results of a single-centered study.

INTRODUCTION: Hip fracture in geriatric patients has a substantial economic impact and represents a major cause of morbidity and mortality in this population. At our institution, a regional anesthesia program was instituted for patients undergoing surgery for hip fracture. This retrospective cohort review examines the effects of regional anesthesia (from mainly after July 2007) vs general anesthesia (mainly prior to July 2007) on morbidity, mortality and hospitalization costs. METHODS: This retrospective cohort study involved data collection from electronic and paper charts of 308 patients who underwent surgery for hip fracture from September 2006 to December 2008. Data on postoperative morbidity, in-patient mortality, and cost of hospitalization (as estimated from data on hospital charges) were collected and analyzed. Seventy-three patients received regional anesthesia and 235 patients received general anesthesia. During July 2007, approximately halfway through the study period, a regional anesthesia and analgesia program was introduced. RESULTS: The average cost of hospitalization in patients who received surgery for hip fracture was no different between patients who receive regional or general anesthesia ($16,789 + 631 vs $16,815 + 643, respectively, P = 0.9557). Delay in surgery and intensive care unit (ICU) admission resulted in significantly higher hospitalization costs. Age, male gender, African American race and ICU admission were associated with increased in-hospital mortality. In-hospital mortality and rates of readmission are not statistically different between the two anesthesia groups. CONCLUSIONS: There is no difference in postoperative morbidity, rates of rehospitalization, in-patient mortality or hospitalization costs in geriatric patients undergoing regional or general anesthesia for repair of hip fracture. Delay in surgery beyond 3 days and ICU admission both increase cost of hospitalization.

Benefits of an oral nutritional supplement on pressure ulcer healing in long-term care residents.

OBJECTIVE: To investigate the effects of an oral nutritional supplement (ONS) plus standard care on the healing of pressure ulcers in long-term nursing home residents in addition to standard care. The ONS (Cubitan, Nutricia Advanced Medical Nutrition) was high in energy and protein, and enriched with arginine, vitamin C and zinc. METHOD: A total of 245 patients with grade II-IV pressure ulcers were enrolled into this open study at 61 long-term-care facilities, which reflect the nursing-home population of Luxembourg and Belgium. Residents received the ONS daily for nine weeks, along with their normal diet or enteral feed and standard pressure care. Pressure ulcer area (mm2) and condition were assessed after three and nine weeks. Data were analysed using ANOVA and expressed as mean +/- SD. RESULTS: The patients' age was 82.2 +/- 10.1 years. Sixty-seven patients (27%) had been previously treated with the ONS. The majority of pressure ulcers were located at the sacrum (54%) and heel (32%). The average intake of the 200 ml ONS was 2.3 +/- 0.56 servings daily, which corresponds to 46 g protein, 6.9 g arginine, 575 mg vitamin C, 87 mg vitamin E and 21 mg zinc. After nine weeks' nutritional support, the average pressure ulcer area reduced significantly from 1580 +/- 3743 mm2 to 743 +/- 1809 mm2, which is a reduction of 53% (p<0.0001). Complete wound closure occurred after three and nine weeks in 7% and 20% of the pressure ulcers respectively. The amount of exudation (assessed subjectively) also decreased after specialised nutritional support (p<0.0001). CONCLUSION: A high-protein ONS enriched with arginine, vitamin C, vitamin E and zinc, when used with standard pressure ulcer care, significantly reduced the mean pressure ulcer area of long-term nursing home residents.

Discovery and Characterization of Novel Nonsubstrate and Substrate NAMPT Inhibitors.

Cancer cells are highly reliant on NAD+-dependent processes, including glucose metabolism, calcium signaling, DNA repair, and regulation of gene expression. Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme for NAD+ salvage from nicotinamide, has been investigated as a target for anticancer therapy. Known NAMPT inhibitors with potent cell activity are composed of a nitrogen-containing aromatic group, which is phosphoribosylated by the enzyme. Here, we identified two novel types of NAM-competitive NAMPT inhibitors, only one of which contains a modifiable, aromatic nitrogen that could be a phosphoribosyl acceptor. Both types of compound effectively deplete cellular NAD+, and subsequently ATP, and produce cell death when NAMPT is inhibited in cultured cells for more than 48 hours. Careful characterization of the kinetics of NAMPT inhibition in vivo allowed us to optimize dosing to produce sufficient NAD+ depletion over time that resulted in efficacy in an HCT116 xenograft model. Our data demonstrate that direct phosphoribosylation of competitive inhibitors by the NAMPT enzyme is not required for potent in vitro cellular activity or in vivo antitumor efficacy. Mol Cancer Ther; 16(7); 1236-45. ©2017 AACR.

Gastro-Intestinal Tolerance and Renal Safety of Protein Oral Nutritional Supplements in Nursing Home Residents: A Randomized Controlled Trial.

BACKGROUND/OBJECTIVE: High protein oral nutritional supplements (ONS) are regularly prescribed to undernourished patients; however usage of these in older adults is being discussed, as their renal function might have declined with age. Therefore, the aim of the current study was to evaluate the effects of 8 week long consumption of high protein ONS on the renal function of nursing home residents in need of supplementation. Furthermore, within the same setup, differences in gastro-intestinal tolerance between a standard and a more concentrated version of an ONS were investigated. DESIGN: Randomized, controlled, single-blind, parallel-group, multi-country trial (NTR2565). SETTING: Nursing home. PARTICIPANTS: 67 nursing home residents in need of ONS (energy-dense, small volume group n=32; standard volume group n=35). INTERVENTION: Protein supplementation was provided by either a standard (200ml, 300kcal, 20g protein) or an energy-dense, small volume (125ml, 300kcal, 18g protein) ONS during the 8 week long study. MEASUREMENTS: Primary outcome was gastro-intestinal tolerance, assessed by daily stool frequency and consistency, and occurrence and intensity of self-reported gastro-intestinal symptoms. Safety was measured via the occurrence of (serious) adverse events, vital signs, as well as liver- and kidney function monitoring. RESULTS: No clinically relevant and, except for flatulence, no statistically significant differences in gastro-intestinal tolerance were observed between groups. No significant difference between groups was found for estimated glomerular filtration rate (eGFR) and urinary albumin/creatinine ratio at baseline and week 8, nor for the changes from baseline. Adverse events and the changes in monitored renal parameters over the study period did not point to a deterioration of renal function. CONCLUSION: High protein ONS seems to be well-tolerated and safe; there is no indication that it affects renal function in nursing home residents, including patients with stage 3 chronic kidney disease, under the conditions tested. Results did not suggest a difference in the effect on renal function between standard and energy-dense small volume ONS format.

Tumorigenic and metastatic properties of two ras-oncogene transfected rat fibrosarcoma cell lines defective in c-jun.

We here report the spontaneous loss of both homologues of the c-jun gene in two cell lines, isolated after transfection of rat embryo fibroblasts with single ras-oncogenes. These cells lines (designated A14 and B25) grow rapidly in vitro, have transformed morphologies and are invasive through reconstituted basal membranes. Both c-jun defective cell lines were found to be tumorigenic and metastatic in athymic mice. Loss of c-jun was paralleled by a dramatic decrease in interstitial collagenase expression, whereas stromelysin mRNA expression in c-jun- A14 and B25 cells was similar to that observed in c-jun+ transformed cell lines. Transient transfection experiments using reporter plasmids showed that stromelysin promoter activity in A14 cells was severely impaired by a point mutation in the -71 to -65 AP-1 motif, and was inhibited by a Jun dominant negative mutant. Gel mobility shift studies demonstrated the presence of a factor in A14 nuclear extracts capable of binding the stromelysin TRE. This factor bound JunB, JunD and Fos antibodies. Our findings suggest that c-Jun is not required for the tumorigenic and metastatic potential of ras-transformed fibrosarcoma cells, and that AP-1 protein(s) lacking c-Jun are capable of activating the stromelysin gene promoter.

Synthesis and structure-activity relationships of a series of novel benzopyran-containing platelet activating factor antagonists.

A class of N-substituted tetrahydrobenzopyrano[3,4-c]pyridines, I, have been identified as antagonists of platelet activating factor (PAF). The structural features essential for PAF binding were determined by systematic modification of three sites in the molecule. While O-alkyl analogues had little effect on binding potency, N-alkyl analogues exhibited a wide range of activity. Structural changes in the core ring system generally resulted in a loss of binding activity. Optimization of the N- and O-substituents resulted in the analogues 25-27 which exhibited Ki values ranging between 131 and 167 nM in a [3H]PAF binding assay. Compound 23 was also active in a model of PAF-induced shock in the mouse following intravenous administration.

N-(acyloxyalkyl)pyridinium salts as soluble prodrugs of a potent platelet activating factor antagonist.

Pyrrolothiazole 4 is a potent antagonist of platelet activating factor-mediated effects in a variety of in vitro and in vivo assays. Despite its positive activity in models of inflammation and septic shock, 4 lacks the aqueous solubility necessary for intravenous administration. This deficit was overcome by conversion of 4 to water-soluble pyridinium prodrugs. A two-step procedure was used to prepare a series of N-(acyloxyalkyl)pyridinium salts, all of which exhibited aqueous solubility of greater than 20 mg/mL. The rate of conversion of these prodrugs to 4 was faster in human plasma than in pH 7 aqueous buffer. This rate difference was shown to be due to serum enzymes since the conversion in plasma was significantly slower in the presence of a serine esterase inhibitor. A strong correlation between prodrug structure and buffer/plasma half-life was established. The N-(acetyloxymethyl)pyridinium prodrug 11 (ABT-299) is currently undergoing clinical evaluation for the treatment of sepsis.

3-(2-(3-Pyridinyl)thiazolidin-4-oyl)indoles, a novel series of platelet activating factor antagonists.

(2RS,4R)-3-(2-(3-Pyridinyl)thiazolidin-4-oyl)indoles represent a new class of potent, orally active antagonists of platelet activating factor (PAF). The compounds were prepared by acylation of the magnesium or zinc salts of substituted indoles with (2RS,4R)-2-(3-pyridinyl)-3-(tert-butoxycarbonyl)thiazolidin-4-oyl chloride. The 3-acylindole moiety functions as a hydrolytically stabilized and conformationally restricted anilide replacement, which imparts a considerable boost in potency to the series. Structure-activity relationships observed for substitution on the indole ring system are discussed. Members of the series compare favorably with other reported PAF antagonists.

Phenoxyphenyl sulfone N-formylhydroxylamines (retrohydroxamates) as potent, selective, orally bioavailable matrix metalloproteinase inhibitors.

A novel series of sulfone N-formylhydroxylamines (retrohydroxamates) have been investigated as matrix metalloproteinases (MMP) inhibitors. The substitution of the ether linkage of ABT-770 (5) with a sulfone group 13a led to a substantial increase in activity against MMP-9 but was accompanied by a loss of selectivity for inhibition of MMP-2 and -9 over MMP-1 and diminished oral exposure. Replacement of the biphenyl P1' substituent with a phenoxyphenyl group provided compounds that are highly selective for inhibition of MMP-2 and -9 over MMP-1. Optimization of the substituent adjacent to the retrohydroxamate center in this series led to the clinical candidate ABT-518 (6), a highly potent, selective, orally bioavailable MMP inhibitor that has been shown to significantly inhibit tumor growth in animal cancer models.

Discovery and evaluation of a series of 3-acylindole imidazopyridine platelet-activating factor antagonists.

Studies conducted with the goal of discovering a second-generation platelet-activating factor (PAF) antagonist have identified a novel class of potent and orally active antagonists which have high aqueous solubility and long duration of action in animal models. The compounds arose from the combination of the lipophilic indole portion of Abbott's first-generation PAF antagonist ABT-299 (2) with the methylimidazopyridine heterocycle moiety of British Biotechnology's BB-882 (1) and possess the positive attributes of both of these clinical candidates. Structure-activity relationship (SAR) studies indicated that modification of the indole and benzoyl spacer of lead compound 7b gave analogues that were more potent, longer-lived, and bioavailable and resulted in the identification of 1-(N, N-dimethylcarbamoyl)-4-ethynyl-3-[3-fluoro-4-[(1H-2-methylimidazo[4,5-c] pyrid-1-yl)methyl]benzoyl]indole hydrochloride (ABT-491, 22 m.HCl) which has been evaluated extensively and is currently in clinical development.

Pharmacology of ABT-491, a highly potent platelet-activating factor receptor antagonist.

ABT-491 (4-ethynyl-N, N-dimethyl-3-[3-fluoro-4-[(2-methyl-1H-imidazo-[4,5-c]pyridin-1-yl)methy l]benzoyl]-1H- indole-1-carboxamide hydrochloride) is a novel PAF (platelet-activating factor) receptor antagonist with a K(i) for inhibiting PAF binding to human platelets of 0.6 nM. Binding kinetics of ABT-491 to the PAF receptor is consistent with a relatively slow off-rate of the antagonist when compared to PAF. Inhibition of PAF binding is selective and is correlated with functional antagonism of PAF-mediated cellular responses (Ca2+ mobilization, priming, and degranulation). Administration of ABT-491 in vivo leads to potent inhibition of PAF-induced inflammatory responses (increased vascular permeability, hypotension, and edema) and PAF-induced lethality. Oral potency (ED50) was between 0.03 and 0.4 mg/kg in rat, mouse, and guinea-pig. When administered intravenously in these species, ABT-491 exhibited ED50 values between 0.005 and 0.016 mg/kg. An oral dose of 0.5 mg/kg in rat provided > 50% protection for 8 h against cutaneous PAF challenge. ABT-491 administered orally was also effective in inhibiting lipopolysaccharide-induced hypotension (ED50 = 0.04 mg/kg), gastrointestinal damage (0.05 mg/kg, 79% inhibition), and lethality (1 mg/kg, 85% vs. 57% survival). The potency of this novel antagonist suggests that ABT-491 will be useful in the treatment of PAF-mediated diseases.

Chemical synthesis and surface activity of lung surfactant phospholipid analogs. III. Chiral N-substituted ether-amide phosphonolipids.

A homologous series of chiral (R) ether-amide phosphonolipid analogs of naturally occurring (R) glycerophospholipids were synthesized and characterized for their interfacial behaviors. The phosphonolipids possess isoteric ether, amide, and phosphonate functions at positions corresponding to the sn-1, sn-2, and sn-3 ester functions, respectively, of naturally occurring glycerophospholipids. All compounds were synthesized with disaturated C16:0 alkyl/acyl moieties to give structural analogy with dipalmitoyl phosphatidylcholine (DPPC), the major glycerophospholipid component of lung surfactant. Further substitutions at the headgroup nitrogen were also used to generate differences in headgroup size and polarity in the synthetic compounds. The surface activity of the ether-amide phospholipids was investigated in terms of adsorption to the air-water interface, together with studies of dynamic respreading after monolayer collapse and surface tension lowering in dynamically compressed spread films and dispersions. Results showed that several ether-amide phosphonolipids had more rapid adsorption and improved dynamic respreading behavior compared to DPPC, plus the ability to lower surface tension into the range of less than 1 to 4 mN/m in spread films and in dispersions under dynamic conditions. In combination with a series of diether phosphonolipids synthetized in a companion study [1], these ether-amide compounds are useful in the development of molecular structure-surface activity correlates for lung surfactant-related materials, and should assist in investigating the specificity of interactions between phospholipids and other pulmonary biological molecules.

Specific nutritional support accelerates pressure ulcer healing and reduces wound care intensity in non-malnourished patients.

OBJECTIVE: We investigated the potential of a high-protein, arginine- and micronutrient-enriched oral nutritional supplement (ONS) to improve healing of pressure ulcers in non-malnourished patients who would usually not be considered for extra nutritional support. METHODS: Forty-three non-malnourished subjects with stage III or IV pressure ulcers were included in a multicountry, randomized, controlled, double-blind, parallel group trial. They were offered 200 mL of the specific ONS or a non-caloric control product three times per day, in addition to their regular diet and standard wound care, for a maximum of 8 wk. Results were compared with repeated-measures mixed models (RMMM), analysis of variance, or Fisher's exact tests for categorical parameters. RESULTS: Supplementation with the specific ONS accelerated pressure ulcer healing, indicated by a significantly different decrease in ulcer size compared with the control, over the period of 8 wk (P