DNA vaccines: an evolving approach to the treatment of allergic disorders

Immunotherapy with protein allergens is effective in modulating the immune response and reducing symptoms in patients with allergic rhinitis and asthma. Unfortunately, the dose of allergen that can be administered to allergic asthmatic patients, who might most benefit from this form of therapy, is frequently limited because of reduced FEV, and safety concerns. Therefore, alternative strategies to identify ways to minimize the allergenicity of immunotherapy while improving the effectiveness are currently being investigated in animal models of asthma and in human subjects with allergic rhinitis. Several DNA-based methods of immunization (CpG DNA, CpG DNA conjugated to a protein allergen, and plasmid DNA) have shown promise in animal models of asthma, and some of these DNA-based therapies have entered phase I/II clinical trials. Furthermore, ongoing large-scale phase III clinical trials will be able to determine whether any of these DNA-based therapies are safe and effective to use in subjects with allergic rhinitis and asthma.