Discovery and Early Clinical Development of an Inhibitor of 5-Lipoxygenase Activating Protein (AZD5718) for Treatment of Coronary Artery Disease.

5-Lipoxygenase activating protein (FLAP) inhibitors attenuate 5-lipoxygenase pathway activity and reduce the production of proinflammatory and vasoactive leukotrienes. As such, they are hypothesized to have therapeutic benefit for the treatment of diseases that involve chronic inflammation including coronary artery disease. Herein, we disclose the medicinal chemistry discovery and the early clinical development of the FLAP inhibitor AZD5718 (12). Multiparameter optimization included securing adequate potency in human whole blood, navigation away from Ames mutagenic amine fragments while balancing metabolic stability and PK properties allowing for clinically relevant exposures after oral dosing. The superior safety profile of AZD5718 compared to earlier frontrunner compounds allowed us to perform a phase 1 clinical study in which AZD5718 demonstrated a dose dependent and greater than 90% suppression of leukotriene production over 24 h. Currently, AZD5718 is evaluated in a phase 2a study for treatment of coronary artery disease.

Initial Clinical Experience with AZD5718, a Novel Once Daily Oral 5-Lipoxygenase Activating Protein Inhibitor.

We evaluated safety, tolerability, pharmacokinetics, and pharmacodynamics of AZD5718, a novel 5-lipooxygenase activating protein (FLAP) inhibitor, in a randomized, single-blind, placebo-controlled, first-in-human (FIH) study consisting of single and multiple ascending dosing (SAD and MAD) for 10 days in healthy subjects. Target engagement was measured by ex vivo calcium ionophore stimulated leukotriene B (LTB4 ) production in whole blood and endogenous leukotriene E (LTE4 ) in urine. No clinically relevant safety and tolerability findings were observed. The AZD5718 was rapidly absorbed and plasma concentrations declined biphasically with a mean terminal half-life of 10-12 h. Steady-state levels were achieved after ∼3 days. After both SADs and MADs, a dose/concentration-effect relationship between both LTB4 and LTE4 vs. AZD5718 exposure was observed with concentration of half inhibition (IC50 ) values in the lower nM range. Based on obtained result, AZD5718 is considered as a suitable drug candidate for future evaluation in patients with coronary artery disease (CAD).

Targeting 5-lipoxygenase-activating protein in asthma and chronic obstructive pulmonary disease.

INTRODUCTION: In asthma and chronic obstructive pulmonary disease (COPD), there is an unmet therapeutic need for the anti-inflammatory therapies, and the identification of therapeutic targets and potent corresponding therapies is necessary. Although inhaled corticosteroids and leukotriene modifiers are most effective in asthma they are still not always capable of appropriately controlling the disease. In COPD, the therapeutic gap is even larger because inhaled corticosteroids and other anti-inflammatory therapies are not beneficial in all disease subsets. AREAS COVERED: The role of the 5-lipoxygenase-activating protein (FLAP) in generating proinflammatory molecules such as leukotrienes is discussed, highlighting, in particular, its potential as a therapeutic target in asthma and COPD. The preclinical data on FLAP inhibitors are discussed. The clinical data on the FLAP inhibitors investigated so far for these diseases are analyzed. EXPERT OPINION: FLAP inhibitors have emerged during the past decade as a promising therapeutic class in asthma and COPD, but there exists only a limited amount of data supporting their efficacy in these diseases. This might be due to the fact that the development of some of the molecules discussed was abandoned. Such therapies might be of particular interest in COPD and in asthma-COPD overlap syndrome.

The effect of GSK2190915, a 5-lipoxygenase-activating protein inhibitor, on exercise-induced bronchoconstriction.

Exercise-induced bronchoconstriction (EIB) describes the condition whereby exercise causes airflow obstruction that lasts for up to 90 minutes without treatment. This double-blind, placebo-controlled, five-way crossover study investigated the dose response and duration of action of a 5-lipoxygenase-activating protein inhibitor, GSK2190915, to inhibit EIB in subjects with asthma. Forty-seven subjects with EIB were enrolled. Exercise challenge testing was scheduled at 2, 9.5, and 24 hours after receiving a single dose of GSK2190915 (10, 50, 100, and 200 mg) or placebo in randomized order. GSK2190915 at 200 and 100 mg significantly attenuated the response to exercise at 2 and 9.5 hours postdose, respectively, compared with placebo. The adjusted mean maximum percentage change from baseline forced expiratory volume at 1 second within 60 minutes postexercise challenge (FEV1 (0-60)) treatment difference for GSK2190915 at 200 mg compared with placebo at 2 hours postdose was 6.30% (95% CI, 3.06, 9.54), corresponding to a 40% attenuation of the placebo response to exercise; the treatment difference between GSK2190915 at 100 mg and placebo at 9.5 hours postdose was 3.49% (95% CI, 1.02, 5.95), corresponding to a 41% attenuation of the placebo response to exercise. No significant effect was seen at 24 hours postdose with any dose; however, investigation of statistically significant treatment-related effects at this time point was limited because of the small fall in adjusted mean FEV1 (0-60) (-7.61%; 95% CI, -10.23, -4.99) after placebo. GSK2190915 may be of benefit in EIB prevention. GSK Clinical Study LPA112025; ClinicalTrials.gov identifier number: NCT00812929.

Effects of a FLAP inhibitor, GSK2190915, in asthmatics with high sputum neutrophils.

Patients with refractory asthma frequently have neutrophilic airway inflammation and respond poorly to inhaled corticosteroids. This study evaluated the effects of an oral 5-lipoxygenase-activating protein (FLAP) inhibitor, GSK2190915, in patients with asthma and elevated sputum neutrophils. Patients received 14 (range 13-16) days treatment with GSK2190915 100 mg and placebo with a minimum 14 day washout in a double-blind, cross-over, randomised design (N = 14). Sputum induction was performed twice pre-dose in each treatment period to confirm sputum neutrophilia, and twice at the end of each treatment period. The primary endpoint was the percentage and absolute sputum neutrophil count, averaged for end-of-treatment visits. GSK2190915 did not significantly reduce mean percentage sputum neutrophils (GSK2190915-placebo difference [95% CI]: -0.9 [-12.0, 10.3]), or mean sputum neutrophil counts (GSK2190915/placebo ratio [95% CI]: 1.06 [0.43, 2.61]). GSK2190915 resulted in a marked suppression (>90%) of sputum LTB4 and urine LTE4, but did not alter clinical endpoints. There were no safety issues. Despite suppressing the target mediator LTB4, FLAP inhibitor GSK2190915 had no short-term effect on sputum cell counts or clinical endpoints in patients with asthma and sputum neutrophilia.

MK886 reduces cerebral amyloid angiopathy severity in TgCRND8 mice.

BACKGROUND: Deposition of amyloid-ß (Aß) in blood vessel walls as cerebral amyloid angiopathy (CAA) is observed in the majority of Alzheimer's disease (AD) brains. Inhibition of the 5-lipoxygenase (5-LOX) pathway has recently been suggested to play a role in reducing parenchymal Aß deposition. However, products of the 5-LOX pathway also activate the peroxisome proliferator-activated receptor (PPAR) family, which promotes clearance of Aß from the brain. METHODS: In the present study, we investigated the effect of MK886, a 5-LOX-activating protein (FLAP) inhibitor and PPARα antagonist, on CAA severity in TgCRND8 mice overexpressing the human Swedish and Indiana amyloid precursor protein mutations. RESULTS: We found that MK886 significantly reduced brain levels of nicastrin and PPARα, but did not affect levels of ß-secretase, apolipoprotein E or low-density lipoprotein receptor-related protein-1. CAA severity and parenchymal plaque load was significantly decreased in both the cortex and hippocampus of mice treated with MK886 compared to control mice. CONCLUSION: These data suggest that 5-LOX and FLAP inhibitors may be useful in the treatment of CAA and AD.

Efficacy, safety and tolerability of GSK2190915, a 5-lipoxygenase activating protein inhibitor, in adults and adolescents with persistent asthma: a randomised dose-ranging study.

BACKGROUND: GSK2190915 is a high affinity 5-lipoxygenase-activating protein inhibitor being developed for the treatment of asthma. The objective of this study was to evaluate GSK2190915 efficacy, dose-response and safety in subjects with persistent asthma treated with short-acting beta2-agonists (SABAs) only. METHODS: Eight-week multicentre, randomised, double-blind, double-dummy, stratified (by age and smoking status), parallel-group, placebo-controlled study in subjects aged ≥12 years with a forced expiratory volume in 1 second (FEV1) of 50-85% predicted. Subjects (n = 700) were randomised to receive once-daily (QD) oral GSK2190915 (10-300 mg), twice-daily inhaled fluticasone propionate 100 µg, oral montelukast 10 mg QD or placebo. The primary endpoint was mean change from baseline (randomisation) in trough (morning pre-dose and pre-rescue bronchodilator) FEV1 at the end of the 8-week treatment period. Secondary endpoints included morning and evening peak expiratory flow, symptom-free days and nights, rescue-free days and nights, day and night-time symptom scores, day and night-time rescue medication use, withdrawals due to lack of efficacy, Asthma Control Questionnaire and Asthma Quality of Life Questionnaire scores. RESULTS: For the primary endpoint, there was no statistically significant difference between any dose of GSK2190915 QD and placebo. However, repeated measures sensitivity analysis demonstrated nominal statistical significance for GSK2190915 30 mg QD compared with placebo (mean difference: 0.115 L [95% confidence interval: 0.00, 0.23], p = 0.044); no nominally statistically significant differences were observed with any of the other doses. For the secondary endpoints, decreases were observed in day-time symptom scores and day-time SABA use for GSK2190915 30 mg QD versus placebo (p ≤ 0.05). No dose-response relationship was observed for the primary and secondary endpoints across the GSK2190915 dose range studied; the 10 mg dose appeared to be sub-optimal. GSK2190915 was associated with a dose-dependent reduction in urinary leukotriene E4. The profile and incidence of adverse events were similar between treatment groups. CONCLUSION: Efficacy was demonstrated for GSK2190915 30 mg compared with placebo in day-time symptom scores and day-time SABA use. No additional improvement on efficacy endpoints was gained by administration of GSK2190915 doses greater than 30 mg. GSK2190915 was well-tolerated. These results may support further studies with GSK2190915 30 mg. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01147744.

The 5-lipoxygenase-activating protein inhibitor, GSK2190915, attenuates the early and late responses to inhaled allergen in mild asthma.

BACKGROUND: GSK2190915, a potent 5-lipoxygenase-activating protein inhibitor, prevents the synthesis of leukotrienes and 5-oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE). OBJECTIVE: To assess the effect of GSK2190915 on the allergen-induced asthmatic responses. METHODS: Nineteen eligible male subjects with mild asthma were enrolled in and completed this four-centre, double-blind, two-way crossover study (ClinicalTrials.gov NCT00748306). Subjects took GSK2190915 100 mg and placebo orally once daily for 5 days in randomized order. On Day 1 and 4 they had a methacholine challenge, on Day 3 they had an inhaled allergen challenge, and on Days 4 and 6 they had sputum induction. RESULTS: GSK2190915 attenuated the early (0-2 h) and late (4-10 h) asthmatic responses to inhaled allergen compared with placebo. There was a statistically significant attenuation of the early asthmatic response (EAR) by GSK2190915; treatment difference of GSK2190915 vs. placebo for the minimum FEV(1) EAR was 0.408 L (0.205, 0.611). There was a statistically significant attenuation of the late asthmatic response (LAR) by GSK2190915; the treatment difference of GSK2190915 vs. placebo for the minimum FEV(1) LAR was 0.229 L (0.041, 0.417). There was a statistically significant attenuation of allergen-induced sputum eosinophil count on Day 4 following GSK2190915: mean treatment difference (95% CI) between GSK2190915 and placebo was -9.95% (-18.15%, -1.77%). Compared with placebo, GSK2190915 100 mg reduced median sputum LTB(4) by > 90% on Days 4 and 6. There was no effect on methacholine PC(20) post allergen. GSK2190915 was generally well tolerated. CONCLUSION AND CLINICAL RELEVANCE: GSK2190915 shows potential as a treatment for patients with asthma.

Involvement of 5-lipoxygenase activating protein in the amyloidotic phenotype of an Alzheimer's disease mouse model.

BACKGROUND: The 5-lipoxygenase enzyme is widely distributed within the central nervous system and its activity is regulated by the presence and availability of another protein, called 5-lipoxygenase activating protein. While previous works have shown that 5-lipoxygenase is involved in the pathogenesis of Alzheimer's disease, no data are available on the role that 5-lipoxygenase activating protein plays in Alzheimer's disease. METHODS: In the present paper, we studied the effect of pharmacologic inhibition of 5-lipoxygenase activating protein on the amyloidotic phenotype of Tg2576 mice. RESULTS: Amyloid ß peptide (Aß) deposition in the brains of mice receiving MK-591, a selective and specific 5-lipoxygenase activating protein inhibitor, was significantly reduced when compared with controls. This reduction was associated with a similar decrease in brain Aß peptides levels. MK-591 treatment did not induce any change in the steady-state levels of amyloid-ß precursor protein, ß-site amyloid precursor protein cleaving enzyme 1 or disintegrin and metalloproteinase domain-containing protein 10. By contrast, it resulted in a significant reduction of the γ-secretase complex, at the protein and message level. Furthermore, in vitro studies confirmed that MK-591 prevents Aß formation by modulating γ-secretase complex levels without affecting Notch signaling. CONCLUSIONS: These data establish a novel functional role for 5-lipoxygenase activating protein in the pathogenesis of Alzheimer's disease-like amyloidosis, and suggest that its pharmacological inhibition could provide a novel therapeutic opportunity for Alzheimer's disease.