n6022 and Asthma

Patients with asthma demonstrate depletion of the endogenous bronchodilator GSNO and upregulation of GSNOR.. An exploratory proof of concept clinical study of N6022 in mild asthma to determine the potential bronchoprotective effects of GSNOR inhibition. Mechanistic studies aimed to provide translational evidence of effect.. Fourteen mild asthma patients were treated with intravenous N6022 (5 mg) or placebo and observed for 7 days, with repeated assessments of the provocative dose of methacholine causing a 20% fall in FEV1 (methacholine PC. In this early phase exploratory proof of concept trial in asthma, N6022 did not significantly alter methacholine PC

Topics: Administration, Intravenous; Adult; Aldehyde Oxidoreductases; Asthma; Benzamides; Bronchial Hyperreactivity; Bronchial Provocation Tests; Bronchoconstrictor Agents; Cross-Over Studies; Double-Blind Method; Female; Forced Expiratory Volume; Humans; Male; Methacholine Chloride; Middle Aged; Placebos; Proof of Concept Study; Pyrroles; S-Nitrosoglutathione; Treatment Outcome; Young Adult

S-nitrosoglutathione (GSNO) serves as a reservoir for nitric oxide (NO) and thus is a key homeostatic regulator of airway smooth muscle tone and inflammation. Decreased levels of GSNO in the lungs of asthmatics have been attributed to increased GSNO catabolism via GSNO reductase (GSNOR) leading to loss of GSNO- and NO- mediated bronchodilatory and anti-inflammatory actions. GSNOR inhibition with the novel small molecule, N6022, was explored as a therapeutic approach in an experimental model of asthma.. Female BALB/c mice were sensitized and subsequently challenged with ovalbumin (OVA). Efficacy was determined by measuring both airway hyper-responsiveness (AHR) upon methacholine (MCh) challenge using whole body plethysmography and pulmonary eosinophilia by quantifying the numbers of these cells in the bronchoalveolar lavage fluid (BALF). Several other potential biomarkers of GSNOR inhibition were measured including levels of nitrite, cyclic guanosine monophosphate (cGMP), and inflammatory cytokines, as well as DNA binding activity of nuclear factor kappa B (NFκB). The dose response, onset of action, and duration of action of a single intravenous dose of N6022 given from 30 min to 48 h prior to MCh challenge were determined and compared to effects in mice not sensitized to OVA. The direct effect of N6022 on airway smooth muscle tone also was assessed in isolated rat tracheal rings.. N6022 attenuated AHR (ED50 of 0.015 ± 0.002 mg/kg; Mean ± SEM) and eosinophilia. Effects were observed from 30 min to 48 h after treatment and were comparable to those achieved with three inhaled doses of ipratropium plus albuterol used as the positive control. N6022 increased BALF nitrite and plasma cGMP, while restoring BALF and plasma inflammatory markers toward baseline values. N6022 treatment also attenuated the OVA-induced increase in NFκB activation. In rat tracheal rings, N6022 decreased contractile responses to MCh.. The significant bronchodilatory and anti-inflammatory actions of N6022 in the airways are consistent with restoration of GSNO levels through GSNOR inhibition. GSNOR inhibition may offer a therapeutic approach for the treatment of asthma and other inflammatory lung diseases. N6022 is currently being evaluated in clinical trials for the treatment of inflammatory lung disease.

Topics: Aldehyde Oxidoreductases; Animals; Asthma; Benzamides; Bronchoconstriction; Female; Inflammation; Mice; Mice, Inbred BALB C; Pyrroles

S-nitrosoglutathione reductase is the primary enzyme responsible for the metabolism of S-nitrosoglutathione (GSNO), the body's main source of bioavailable nitric oxide. Through its catabolic activity, GSNO reductase (GSNOR) plays a central role in regulating endogenous S-nitrosothiol levels and protein S-nitrosation-based signaling. By inhibiting GSNOR, we aim to increase pulmonary GSNO and induce bronchodilation while reducing inflammation in lung diseases such as asthma. To support the clinical development of N6022, a first-in-class GSNOR inhibitor, a 14-day toxicology study was conducted. Sprague-Dawley rats were given 2, 10 or 50 mg/kg/day N6022 via IV administration. N6022 was well tolerated at all doses and no biologically significant adverse findings were noted in the study up to 10 mg/kg/day. N6022-related study findings were limited to the high dose group. One male rat had mild hepatocellular necrosis with accompanying increases in ALT and AST and several male animals had histological lung assessments with a slight increase in foreign body granulomas. Systemic exposure was greater in males than females and saturation of plasma clearance was observed in both sexes in the high dose group. Liver was identified as the major organ of elimination. Mechanistic studies showed dose-dependent effects on the integrity of a rat hepatoma cell line.

Topics: Alanine Transaminase; Aldehyde Oxidoreductases; Alkaline Phosphatase; Animals; Aspartate Aminotransferases; Asthma; Benzamides; Bile; Cell Line, Tumor; Cell Survival; Drug Evaluation, Preclinical; Enzyme Inhibitors; Feces; Female; Glutathione; Liver; Lung; Male; Pyrroles; Rats; Rats, Sprague-Dawley

The enzyme S-nitrosoglutathione reductase (GSNOR) is a member of the alcohol dehydrogenase family (ADH) that regulates the levels of S-nitrosothiols (SNOs) through catabolism of S-nitrosoglutathione (GSNO). GSNO and SNOs are implicated in the pathogenesis of many diseases including those in respiratory, gastrointestinal, and cardiovascular systems. The pyrrole based N6022 was recently identified as a potent, selective, reversible, and efficacious GSNOR inhibitor which is currently in clinical development for acute asthma. We describe here the synthesis and structure-activity relationships (SAR) of novel pyrrole based analogs of N6022 focusing on carboxamide modifications on the pendant N-phenyl moiety. We have identified potent and novel GSNOR inhibitors that demonstrate efficacy in an ovalbumin (OVA) induced asthma model in mice.

Topics: Acute Disease; Aldehyde Oxidoreductases; Animals; Anti-Asthmatic Agents; Asthma; Benzamides; Enzyme Inhibitors; Humans; Male; Mice; Ovalbumin; Pyrroles; S-Nitrosoglutathione; S-Nitrosothiols; Structure-Activity Relationship

The pyrrole based N6022 was recently identified as a potent, selective, reversible, and efficacious S-nitrosoglutathione reductase (GSNOR) inhibitor and is currently undergoing clinical development for the treatment of acute asthma. GSNOR is a member of the alcohol dehydrogenase family (ADH) and regulates the levels of S-nitrosothiols (SNOs) through catabolism of S-nitrosoglutathione (GSNO). Reduced levels of GSNO, as well as other nitrosothiols (SNOs), have been implicated in the pathogenesis of many diseases including those of the respiratory, cardiovascular, and gastrointestinal systems. Preservation of endogenous SNOs through GSNOR inhibition presents a novel therapeutic approach with broad applicability. We describe here the synthesis and structure-activity relationships (SAR) of novel pyrrole based analogues of N6022 focusing on removal of cytochrome P450 inhibition activities. We identified potent and novel GSNOR inhibitors having reduced CYP inhibition activities and demonstrated efficacy in a mouse ovalbumin (OVA) model of asthma.

Topics: Aldehyde Oxidoreductases; Animals; Asthma; Benzamides; Cytochrome P-450 Enzyme Inhibitors; Cytochrome P-450 Enzyme System; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Design; Drug Evaluation, Preclinical; Enzyme Inhibitors; Humans; Imidazoles; Lung; Mice; Molecular Structure; Molecular Targeted Therapy; No-Observed-Adverse-Effect Level; Pyrroles; Receptors, Opioid, delta; S-Nitrosoglutathione; Structure-Activity Relationship