This is a pivotal, 12-month, randomized, sham controlled, parallel group, multicenter, double blind study with an allocation ratio of 1:1. The study population is children between the ages 6 to 17 years, with mild to moderate persistent asthma. The purpose of the study is to determine whether the CREON2000A, an environmental control device, will decrease asthma severity, as measured by the Composite Asthma Severity Index (CASI), in children with mild to moderate persistent allergic asthma over a twelve month period.

The pilot study (Protocol #PA-01-052; Health Effects of CREON2000 in Asthmatic Children. IB ID# GI 1001) offered preliminary evidence that the CREON2000A system may be beneficial in asthma. This study is a follow-up, using children, aged 6 to 17 with mild to moderate persistent asthma, as the subjects of the study. Children are usually treated with fewer controller medications and have fewer confounding co-morbidities making it more likely to detect a therapeutic benefit from an environmental intervention. The study will involve 4 study site visits, 2 home visits, and 7 phone calls. Adjustment of asthma therapy by the site clinician will occur at baseline (Visit 1) and at each follow-up office visit after Visit 1 using a modified algorithm based on the National Asthma Education and Prevention Program Expert Panel Report 3 (NAEPP EPR3) guidelines. Enrollment will be over 18 months. The study duration for each subject will be 12 months.

Inclusion criteria

1. Males and Females ages 6.0 to 17.0 years.
2. Subjects with a physician diagnosis of mild or moderate persistent asthma.
3. FEV1 ≥ 60% predicted with ≥ 12% improvement after bronchodilator therapy.
4. Must have evidence of; 1) serum specific IgE (immunocap) ≥ .35 or 2) a positive skin prick test to one or more common indoor allergens including standardized house dust mite, cat, dog, cockroach, mouse in the past.

Exclusion criteria

1. Current smokers
2. Passive exposure to environmental tobacco smoke at home or active fireplaces and other sources of air particulates (wood burning stoves, kerosene heaters) at home.
3. Diagnosed by a physician with a chronic lung disease other than asthma.
4. Upper or lower respiratory infection within four weeks prior to enrollment.
5. Known to have any other chronic illness (besides asthma) that is not well controlled at the time of screening (Visit 1).
6. History of a life threatening asthma attack requiring cardiopulmonary support, intubation with ventilatory support, hospitalization in an intensive care unit or hospitalization for asthma within 6 months preceding study screening (Visit 1).
7. Participation in another investigational drug/device study within the past 3 months (not including chart or observational studies)