View clinical trials related to Asthma.
Filter by:To continue to evaluate risk factors heretofore determined to be important predictors of chronic respiratory symptoms, diagnosis of asthma, and alterations in expected levels of lung function in children and adolescents in a new population of young adult women.
To determine the natural history, etiology, and interrelationships of emphysema, chronic bronchitis, asthma, and related airways obstructive diseases. Also, to determine the relationship of acute lower respiratory tract illnesses in infants and children to the development of subsequent chronic lung disorders.
To identify risk factors for idiopathic dilated cardiomyopathy and to examine prognostic factors over a follow-up period of two to three years.
To determine morbidity and mortality from cardiovascular disease among American Indians and to compare cardiovascular disease risk factor levels among Indian groups living in different geographic areas.
To investigate coronary heart disease and stroke among American men of Japanese ancestry who were living on the island of Oahu in 1965. Morbidity and mortality surveillance of the original cohort is continuing.
This study will examine how allergen immunotherapy (allergy shots) works to reduce or prevent reactions to allergens such as pollen, dust or cat dander. Certain T cells (types of white blood cells) called Th2 cells produce substances that generate allergies. Other T cells called Th1 cells produce substances that have opposite effects. This study will determine if allergy shots change the immune response to allergens by reducing the number of Th2 cells or by changing them into Th1 cells. A better understanding of how this treatment works may help scientists develop more effective allergy therapies. People between 18 and 50 years of age who have had allergic asthma for at least 1 year may participate in this study. Candidates' medical, allergy and medication histories will be reviewed, and they will have a physical examination, including routine blood tests, urinalysis, electrocardiogram (EKG), and lung function test. Blood will also be drawn to test T cell response to allergens, and 12 skin tests (similar to a tuberculosis skin test) will be done to test for sensitivity to various allergens. Participants will be admitted to the Clinical Center for 1 to 2 days for rush therapy (see below). They will have a brief history and physical examination. A heparin lock (thin plastic tube similar to an intravenous line) will be placed in an arm vein. They will then undergo the following procedures: - Rush/Cluster Immunotherapy - An allergen is given in increasing doses over 2 to 5 weeks. During rush therapy, the dose is increased rapidly over 1 to 2 days until a moderate level dose is reached. To reduce the chance of an allergic reaction, patients take prednisone, cetirizine (Zyrtec® (Registered Trademark)), ranitidine (Zantac® (Registered Trademark)) and montelukast (Singular® (Registered Trademark)) starting 24 hours before treatment begins until rush therapy ends. After discharge on the third day, patients return to the clinic once a week for the next 2 to 5 weeks for cluster therapy, in which the dose is increased more gradually to a maintenance level. - Maintenance Immunotherapy - Participants receive 12 weekly injections at the maintenance dose. Blood is drawn during one visit between weeks 2 and 7 of maintenance therapy. - Follow-up Visits - Patients return to the clinic 2 and 3 weeks after the last maintenance dose for blood draws and evaluations. In addition, a "late-phase" allergen skin test is done at the 3-week follow-up to compare reaction results with those from the test done at the screening visit. - End-of-Study Visit - 12 to 16 weeks after the last allergy shot, patients return for a final blood draw and brief evaluation.
Asthma is a chronic inflammatory disorder of the airways characterized by reversible airflow obstruction. Fourteen million persons (6.4%) in the United States report having asthma, and from 1980 to 1994 the prevalence of self-reported asthma in the United States increased by 75%. A major factor in the pathogenesis of asthma is the development of an allergic inflammatory response to inhaled antigens. Interleukin-4 (IL-4) plays a key role in this response by promoting IgE production, upregulating IgE receptors, upregulating adhesion receptors such as VCAM-1, promoting Th2 cell development and increasing mucus secretion. Soluble recombinantly produced IL-4R (sIL-4R) has been shown to bind and inactivate IL-4, both in vitro and in animal models. As part of a multicenter trial, 20 subjects at the NIH site will receive 0.9 mg., 1.8 mg. sIL-4R or placebo once weekly for 12 weeks in a double blind placebo controlled study. Study drug will be delivered via the AERx aerosol drug delivery device. The primary objective of the study will be to evaluate efficacy as measured by FEV1. Secondary objectives will include changes in FVC, FEF 27-75, peak flow, bronchodilator usage, asthma symptoms, quality of life scores, immunologic and inflammatory markers, pharmacokinetics, safety and immunogenicity. The study population will consist of moderate to severe asthmatics on (Beta)-agonist monotherapy with an FEV1 of 50-80% of predicted. After 12 weeks of study drug, subjects will be followed for an additional 8 weeks.
Asthma is a chronic inflammatory disorder of the airways characterized by reversible airflow obstruction. Fourteen million people (6.4%) in the United States report having asthma, and from 1980 to 1994 the prevalence of self-reported asthma in the United States increased 75%. Interleukin-4 (IL-4) plays a key role in this response by promoting IgE production, upregulating IgE receptors, upregulating adhesion receptors such as VCAM-1, promoting Th2 cell development and promoting mucus secretion. A soluble form of the receptor for IL-4 (IL-4R) that has antagonist activity has been developed for clinical use. Soluble IL-4R acts by competing with endogenous cell bound IL-4R for free IL-4, thus inhibiting IL-4 function. IL-4 is required for the development of allergen specific Th2 memory cells. Less well understood are the factors required for maintenance of Th2 responses. The maintenance of polarized Th2 responses to allergens have been postulated to require IL-4 itself, by acting as an anti-apoptotic/survival factor or by differentiating naive allergen specific T cells to the Th2 phenotype. Subjects on sIL-4 therapy represent a unique patient group that possess allergen specific Th2 cells, but in which the capacity for IL-4 to promote further Th2 cell survival or differentiation has been blocked. This is a single site adjunct study proposed to study subjects ages 14 years and older who are enrolled at the NIH Clinical Center on a multicenter trial of IL-4R in moderate to severe asthma (Phase II Efficacy Study of Aerosolized Recombinant Human IL-4 Receptor in Asthma). A maximum of 40 subjects will be enrolled. We hypothesize that effective blocking of such Th2 priming would result in a decreased frequency of both allergen specific Th2 cells as well as mitogen activated Th2 cells. Determination of the fate of Th2 cell responses during long term IL-4R therapy may have important implications both for future development of anti-cytokine therapies as well as for understanding the T cell biology of allergic diseases and asthma.
The proposed study is a phase II clinical trial of TNFR:Fc therapy in a segmental allergen bronchoprovocation model of atopic asthma. The goal of this study is to assess whether inhibition of tumor necrosis factor (TNF) bioactivity can attenuate airway inflammation in mild-to-moderate allergic asthmatics. This protocol will utilize a randomized, double-blind, placebo-controlled trial design. TNF bioactivity will be inhibited via systemic administration (e.g., subcutaneous injection) of a dimeric fusion protein consisting of the extracellular ligand binding domain of the 75-kilodalton TNF receptor linked to the Fc portion of human IgG1 (TNFR:Fc, Immunex). The data generated by this study will address the utility of anti-TNF therapy for patients with asthma.
Asthma is the third leading cause of preventable admissions to the hospital in the United States. Deaths and diseases associated with asthma increase every year. Asthma is a disorder of airway inflammation. There are several factors thought to play a role in the process of inflammation. In this study researchers are particularly interested in studying a factors known as TNF (tumor necrosis factor) and the sites where this factor attaches called receptors. Another factor associated with receptor processing is called aminopeptidase-like protein. It may be involved in the relationship between TNF, it's receptors, and inflammation. In order to understand the relationship between these factors, researchers plan to simulate an allergic reaction in the lungs and airways of patients participating in the study. By doing this they can collect and study the factors causing airway inflammation. Samples collected from patients with asthma will be compared to samples from volunteers without asthma. Patients and volunteers participating in this study will not directly benefit from this research. However, the study may help researchers understand the causes and processes involved in asthma. In addition, the study may lead to the development of new treatments for asthma and airway inflammation.