Omalizumab for severe allergic asthma: dollars and sense

Acute exacerbations of asthma: epidemiology, biology and the exacerbation-prone phenotype

Asthma is a highly prevalent chronic respiratory disease affecting 300 million people world-wide. A significant fraction of the cost and morbidity of asthma derives from acute care for asthma exacerbations. In the United States alone, there are approximately 15 million outpatient visits, 2 million emergency room visits, and 500,000 hospitalizations each year for management of acute asthma. Common respiratory viruses, especially rhinoviruses, cause the majority of exacerbations in children and adults. Infection of airway epithelial cells with rhinovirus causes the release of pro-inflammatory cytokines and chemokines, as well as recruitment of inflammatory cells, particularly neutrophils, lymphocytes, and eosinophils. The host response to viral infection is likely to influence susceptibility to asthma exacerbation. Having had at least one exacerbation is an important risk factor for recurrent exacerbations suggesting an 'exacerbation-prone' subset of asthmatics. Factors underlying the 'exacerbation-prone' phenotype are incompletely understood but include extrinsic factors: cigarette smoking, medication non-compliance, psychosocial factors, and co-morbidities such as gastroesophageal reflux disease, rhinosinusitis, obesity, and intolerance to non-steroidal anti-inflammatory medications; as well as intrinsic factors such as deficient epithelial cell production of the anti-viral type I interferons (IFN-alpha and IFN-beta). A better understanding of the biologic mechanisms of host susceptibility to recurrent exacerbations will be important for developing more effective preventions and treatments aimed at reducing the significant cost and morbidity associated with this important global health problem.

Biologics in asthma: difficulties and drawbacks

BACKGROUND

Biologics have become an increasingly important class of therapeutic compounds in a variety of immune and/or inflammatory diseases. Patients with severe uncontrolled asthma represent a significant unmet need.

METHODS

This review gives some examples of the complex use of biologics in asthma.

RESULTS/CONCLUSIONS

It is very difficult to predict the efficacy of biologics in severe asthma and only one monoclonal antibody to date has been found to be effective and approved by both the FDA and European Medicines Agency (EMEA) for the treatment of difficult allergic asthma. New pathways may prove to be of importance for the development of biologics. Biologics are not devoid of side effects, which can, although not always, be predicted from their mechanism of action. These include hypersensitivity reactions, which need to be better understood to prevent and control them. Finally, biologics should be cost-effective. This review gives some examples of the complex use of biologics in asthma.

Advances in the care of adults with asthma and allergy in 2007

In 2007 the National Asthma Education and Prevention Program published the Expert Panel Report 3, updating its 1997 and 2002 guidelines for the diagnosis and management of asthma with new emphasis on assessment and attainment of control. This review focuses on the Journal articles published in 2007 pertaining to risk and impairment in adult asthma and interventions to improve its control.

Advances in pediatric asthma in 2007

This year's summary focuses on recent advances in pediatric asthma as reported in 2007 publications in the Journal. This past year, new National Asthma Education and Prevention Program asthma guidelines were released with a special emphasis on new information in pediatric asthma. Journal theme issues in 2007 included the revised National Asthma Education and Prevention Program asthma guidelines, the accomplishments of the National Institutes of Health asthma networks, and focused discussions on environmental allergens, neutrophils, eosinophils, T cells, and epithelial cells, all of which affect pediatric asthma. The new asthma guidelines emphasize several key terms including severity, control, impairment, risk, and responsiveness that are relevant for advancing the care of children with asthma. This review highlights journal articles that relate to these guideline topics.