A phase IIa proof-of-concept, placebo-controlled, randomized, double-blind, crossover, single-dose clinical trial of a new class of bronchodilator for acute asthma.

BACKGROUND: This study evaluates a novel bronchodilator, S1226, for its efficacy in reversing allergen-induced bronchoconstriction in subjects with mild, allergic asthma. S1226 is a new class of bronchodilator that is an aerosol/vapor/gas mixture combining pharmacological and biophysical principles for a novel mode of action. It contains a potent bronchodilator gas (carbon dioxide or CO2) and nebulized perflubron (a synthetic surfactant possessing mucolytic properties). It has demonstrated rapid reversal of allergen-induced bronchoconstriction in an ovine study model. METHODS: This was a phase IIa proof-of-concept, placebo-controlled, randomized, double-blind, crossover single-dose clinical trial to evaluate the safety, tolerability, and efficacy of S1226 (8% CO2) administered by nebulization following an allergen-induced early asthmatic response in 12 subjects with mild, allergic asthma. Primary safety endpoints were adverse events, vital signs, pulse oximetry, and spirometry. Efficacy endpoints included bronchodilator response (measured as the forced expiratory volume in 1 s or FEV1) over time, the area under the curve of FEV1 for the early asthmatic response over time, and achievement of responder status, defined as a 12% improvement after the allergen challenge. RESULTS: No significant safety issues were observed. All adverse events were non-serious, mild, and transient. There was a statistically significant decrease in peripheral blood oxygenation levels over time in the placebo group following allergen inhalation, whereas blood oxygenation was maintained at normal levels in the S1226-treated subjects (P = 0.028). This effect was greatest 5 min after start of treatment (P < 0.001). The recovery rate was faster but not significantly so (P = 0.272) for S1226 compared to the placebo at earlier time points (5, 10, and 15 min), as assessed by ≥12% reversal of FEV1. The recovery of FEV1 over time was significantly greater (P = 0.04) with S1226 compared to the placebo. CONCLUSIONS: S1226 was safe, tolerated well, and provided bronchodilation and improved blood oxygenation in subjects with mild atopic asthma following allergen-induced bronchoconstriction. Additional studies to optimize the therapeutic response are indicated. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02334553 . Registered on 12 November 2014.

Efficacy and safety of multiple doses of QGE031 (ligelizumab) versus omalizumab and placebo in inhibiting allergen-induced early asthmatic responses.

BACKGROUND: Omalizumab is an established anti-IgE therapy for the treatment of allergic diseases that prevents IgE from binding to its receptor. QGE031 is an investigational anti-IgE antibody that binds IgE with higher affinity than omalizumab. OBJECTIVE: This study compared the effects of QGE031 with those of omalizumab on clinical efficacy, IgE levels, and FcεRI expression in a clinical model of allergic asthma. METHODS: Thirty-seven patients with mild allergic asthma were randomized to subcutaneous omalizumab, placebo, or QGE031 at 24, 72, or 240 mg every 2 weeks for 10 weeks in a double-blind, parallel-group multicenter study. Inhaled allergen challenges and skin tests were conducted before dosing and at weeks 6, 12, and 18, and blood was collected until 24 weeks after the first dose. RESULTS: QGE031 elicited a concentration- and time-dependent change in the provocative concentration of allergen causing a 15% decrease in FEV1 (allergen PC15) that was maximal and approximately 3-fold greater than that of omalizumab (P = .10) and 16-fold greater than that of placebo (P = .0001) at week 12 in the 240-mg cohort. Skin responses reached 85% suppression at week 12 in the 240-mg cohort and were maximal at week 18. The top doses of QGE031 consistently suppressed skin test responses among subjects but had a variable effect on allergen PC15 (2-fold to 500-fold change). QGE031 was well tolerated. CONCLUSION: QGE031 has greater efficacy than omalizumab on inhaled and skin allergen responses in patients with mild allergic asthma. These data support the clinical development of QGE031 as a treatment of asthma.

A nonsteroidal glucocorticoid receptor agonist inhibits allergen-induced late asthmatic responses.

RATIONALE: Effective antiinflammatory therapies are needed for the treatment of asthma, but preferably without the systemic adverse effects of glucocorticosteroids. OBJECTIVES: We evaluated the effect of an inhaled nonsteroidal glucocorticoid receptor agonist, AZD5423, on allergen-induced responses. METHODS: Twenty subjects with mild allergic asthma were randomized to receive 7 days of treatment with nebulized AZD5423 (75 or 300 µg) once daily, budesonide 200 µg twice daily via Turbuhaler, or placebo in a double-blind, four-period, crossover design study. Allergen challenge was performed on Day 6. MEASUREMENTS AND MAIN RESULTS: FEV1 was measured repeatedly for 7 hours after allergen challenge for early and late asthmatic responses. Sputum inflammatory cells was measured before and at 7 and 24 hours after allergen challenge, and methacholine airway responsiveness was measured before and 24 hours after allergen challenge. AZD5423 significantly attenuated the fall in FEV1 during the late asthmatic response (both doses led to an 8.7% fall) versus placebo (14% fall) (P < 0.05) with no effect of budesonide (12.5% fall) versus placebo (P > 0.05). There was no effect on the fall in FEV1 during early asthmatic response. AZD5423 300 and 75 µg significantly attenuated allergen-induced sputum eosinophilia by 63 and 61% at 7 hours, respectively, and by 46 and 34% at 24 hours after allergen challenge, respectively, versus placebo (all P < 0.05). Budesonide did not reduce allergen-induced sputum eosinophilia versus placebo. AZD5423 at 300 µg significantly attenuated allergen-induced airway hyperresponsiveness at 24 hours after allergen challenge versus placebo (P < 0.05). Both doses of AZD5423 were well tolerated. CONCLUSIONS: Seven-day treatment with inhalation of the nonsteroidal glucocorticoid receptor agonist AZD5423 effectively reduced allergen-induced responses in subjects with mild allergic asthma. Clinical trial registered with www.clinicaltrials.gov (NCT01225549).

Serine proteases decrease intestinal epithelial ion permeability by activation of protein kinase Czeta.

Epithelial permeability to ions and larger molecules in the gut is essential for fluid balance, and its dysregulation contributes to intestinal pathology. We investigated the effect of digestive serine proteases on epithelial paracellular permeability. Trypsin, chymotrypsin, and elastase elicited sustained increases in transepithelial resistance (R(TE)) in polarized monolayers of three intestinal epithelial cell lines. This effect was reflected by decreases in paracellular conductances of Na+ and Cl- and a concomitant decrease in permeability to 3,000 molecular weight dextran. The enzyme activities of the proteases were required, yet activators of known protease-activated receptors (PARs) did not reproduce the effect of these proteases on R(TE). PKCzeta isoform-specific inhibitor significantly reduced the trypsin-induced increase in R(TE) whereas PKCzeta activity was increased in cells treated with trypsin and chymotrypsin compared with control cells; this activity was reduced to control levels in the presence of PKCzeta-specific inhibitor. Ca2+ chelators and pharmacological inhibitors of cell signaling support the role for PKCzeta in the protease-induced effect. Finally, we showed that treatment with the serine proteases increased occludin immunostaining and zonula occludin-1 coimmunoprecipitation with occludin in the detergent-insoluble fraction of cell lysates, and these increases were ablated by pretreatment with PKCzeta-specific inhibitor. This finding indicates increased insertion of occludin into the cell junctional complex. These data demonstrate a role for serine proteases in the facilitation of epithelial barrier function through a mechanism that is independent of PARs and is mediated by activation of PKCzeta.

Apical trypsin increases ion transport and resistance by a phospholipase C-dependent rise of Ca2+.

We investigated the mechanisms by which serine proteases alter lung fluid clearance in rat lungs and vectorial ion transport in airway and alveolar epithelial cells. Inhibition of endogenous protease activity by intratracheal instillation of soybean trypsin inhibitor (SBTI) or alpha(1)-antitrypsin decreased amiloride-sensitive lung fluid clearance across rat fluid-filled lungs; instillation of trypsin partially restored this effect. Gelatin zymography demonstrated SBTI-inhibitable trypsin-like activity in rat lung lavage fluid. Apical trypsin and human neutrophil elastase, but not agonists of protease activated receptors, increased Na(+) and Cl(-) short-circuit currents (I(sc)) and transepithelial resistance (R(TE)) across human bronchial and nasal epithelial cells and rat alveolar type II cells, mounted in Ussing chambers, for at least 2 h. The increase in I(sc) was fully reversed by amiloride and glibenclamide. The increase in R(TE) was not prevented by ouabain, suggesting that trypsin decreased paracellular conductance. Apical trypsin also induced a transient increase in intracellular Ca(2+) in human airway cells; treatment of these cells with BAPTA-AM mitigated the trypsin-induced increases of intracellular Ca(2+) and of I(sc) and R(TE). Increasing intracellular Ca(2+) in airway cells with either ionomycin or thapsigargin reproduced the increase in I(sc), whereas inhibitors of phospholipase C (PLC) prevented the increases in both Ca(2+) and I(sc). These data indicate trypsin-like proteases and elastase, either present in lung cells or released by inflammatory cells into the alveolar space, play an important role in the clearance of alveolar fluid by increasing ion transport and paracellular resistance via a PLC-initiated rise of intracellular Ca(2+).