Dual tachykinin NK1/NK2 antagonist DNK333 inhibits neurokinin A-induced bronchoconstriction in asthma patients.

Inhalation of neurokinin A (NKA) causes bronchoconstriction in patients with asthma. In vitro both tachykinin NK1 and NK2 receptors can mediate airway contraction. In this study the authors examined the effects of a single dose of the dual tachykinin NK1/NK2 receptor antagonist, DNK333, on NKA-induced bronchoconstriction in asthma. A total of 19 male adults with mild asthma completed a randomised, double-blind, placebo-controlled crossover trial. Increasing concentrations of NKA (3.3x10(-9) to 1.0x10(-6) mol x mLP(-1)) were inhaled at 1 and 10 h intervals after a single oral dosing with either DNK333 (100 mg) or a placebo. It was observed that DNK333 did not affect baseline lung function but did protect against NKA-induced bronchoconstriction in those patients. The mean log10 provocative concentration causing a 20% fall in forced expiratory volume in one second for NKA was -5.6 log10 mol x mL(-1) at 1 h after DNK333 treatment and -6.8 log10 mol x mL(-1) after placebo. This was equivalent to a difference of 4.08 doubling doses, which decreased to a difference of 0.90 doubling doses 10 h after treatment. The results shown in this report indicate that DNK333 blocks neurokinin A-induced bronchoconstriction in patients with asthma.

The effects of regular inhaled formoterol and budesonide on preformed Th-2 cytokines in mild asthmatics.

In a recent placebo-controlled study in mild atopic asthmatics, we observed a significant decrease in eosinophils in the bronchial submucosa, after 2 months oftreatment with inhaled formoterol and budesonide. Biopsy material from each treatment group; formoterol (24 microg bid), budesonide (400 microg b. i. d.) and placebo has been further assessed to investigatethe role of Th-2 cytokines by immunohistochemistry using Mabs to eosinophils as an index of inflammation, IL-4 and IL-5. Treatment with formoterol significantly reduced the number of eosinophils (EG2+) in the submucosa and epithelium, but this was not paralleled by changes in cytokine immunoreactivity In contrast, treatment with budesonide significantly reduced both the number of eosinophils (EG2+) and immunoreactivity for IL-4 and IL-5 in the submucosa. Thus, while budesonide has effects on cytokines involved in eosinophil recruitmentthis explanation does not apply tothe eosinopaenia observed with the long-acting beta2 adrenoreceptor agonist formoterol.

Omalizumab, anti-IgE recombinant humanized monoclonal antibody, for the treatment of severe allergic asthma.

BACKGROUND: A recombinant humanized anti-IgE mAb, omalizumab, forms complexes with free IgE, blocking its interaction with mast cells and basophils; as a consequence, it might be effective in the treatment of asthma. OBJECTIVE: The purpose of this study was to evaluate the efficacy and safety of omalizumab in the treatment of inhaled corticosteroid-dependent asthma. METHODS: In this phase III, double-blinded, placebo-controlled trial, 525 subjects with severe allergic asthma requiring daily inhaled corticosteroids were randomized to receive placebo or omalizumab subcutaneously every 2 or 4 weeks, depending on baseline IgE level and body weight. Inhaled corticosteroid doses were kept stable over the initial 16 weeks of treatment and tapered during a further 12-week treatment period. RESULTS: Omalizumab treatment resulted in significantly fewer asthma exacerbations per subject and in lower percentages of subjects experiencing an exacerbation than placebo treatment during the stable steroid phase (0.28 vs 0.54 [P =.006] and 14.6% vs 23.3% [P =.009], respectively) and during the steroid reduction phase (0.39 vs 0.66 [P =.003] and 21.3% vs 32.3% [P =.004], respectively). Beclomethasone dipropionate reduction was significantly greater with omalizumab treatment than with placebo (median 75% vs 50% [P <.001]), and beclomethasone dipropionate discontinuation was more likely with omalizumab (39.6% vs 19.1% [P <.001]). Improvements in asthma symptoms and pulmonary function occurred along with a reduction in rescue beta-agonist use. Omalizumab was well tolerated, with an adverse-events profile similar to that of placebo. CONCLUSION: The addition of omalizumab to standard asthma therapy reduces asthma exacerbations and decreases inhaled corticosteroid and rescue medication use.

Recombinant humanized mAb-E25, an anti-IgE mAb, in birch pollen-induced seasonal allergic rhinitis.

BACKGROUND: Allergic rhinitis is a common condition often requiring treatment. OBJECTIVE: We evaluated whether recombinant humanized (rhu)mAb-E25, a recombinant humanized construct of a murine antibody that binds to circulating IgE, could control symptoms and reduce intake of concomitant medication in seasonal allergic rhinitis (SAR) induced by birch pollen if given subcutaneously in a dose schedule predicted to reduce serum free IgE levels below 25 ng/mL. METHODS: We randomly assigned 251 adult subjects with a history of SAR and a positive skin test response to birch pollen to receive 300 mg of rhumAb-E25 or placebo given 2 or 3 times during the season, depending on baseline IgE levels. The primary efficacy variable was the subject's average daily nasal symptom severity score (sneezing, itching, runny, and stuffy nose) from diary data collected over the double-blind treatment period. Secondary efficacy variables included the average number of rescue antihistamine tablets per day, the proportion of days with any SAR medication use, and rhinoconjunctivitis-specific quality of life (QOL). RESULTS: Significant between-treatment differences in favor of rhumAb-E25 were observed in average daily nasal symptom severity scores, the average number of tablets of rescue antihistamines per day, the proportion of days with any SAR medication use, and all domains of QOL. Serum-free IgE levels were markedly lower in rhumAb-E25-treated subjects and were associated with clinical effectiveness. Recombinant humanized mAb-E25 was well tolerated. No anti-rhumAb-E25 antibodies were detected. CONCLUSION: Compared with placebo, rhumAb-E25 was safe and effective in controlling birch pollen-induced SAR symptoms, with less concomitant medication use and improved QOL. This study shows the therapeutic potential of anti-IgE antibody in SAR.