A CONTROLLED TRIAL OF IMMUNOTHERAPY FOR ASTHMA IN ALLERGIC CHILDREN

Background Injections of allergens are widely prescribed for patients with asthma, but little is known about the effectiveness of immunother apy. Methods We conducted a double-blind, placebo-controlled trial of multiple-allergen immunotherapy in 121 allergic children with moderate -to-severe, perennial (year-round) asthma. The children, who required daily medication for their asthma, were randomly assigned to receive s ubcutaneous injections of either a mixture of up to seven aeroallergen extracts or a placebo. Maintenance injections were continued for 18 m onths or longer. Medications were adjusted every two to three weeks on the basis of peak flow rates and symptoms. The principal outcome was the daily medication score. Bronchial sensitivity to methacholine (the concentration provoking a 20 percent decrease in the forced expirator y volume in one second [PC20]) was measured twice yearly. Results The median medication score declined from 5.4 to 4.9 in the immunotherapy group (P<0.001) and from 5.2 to 5.0 in the placebo group (P<0.001), bu t there was no significant difference between the groups (P>0.6). The number of days on which oral corticosteroids were used was similar in the two groups. Partial or complete remission of asthma occurred in 31 percent of the immunotherapy group and in 28 percent of the placebo g roup (P>0.5). There was no difference between the groups in the use of medical care, symptoms, or peak flow rates. The median PC20 increased significantly in both groups, but again with no difference between th e two groups. Conclusions Immunotherapy with injections of allergens f or over two years was of no discernible benefit in allergic children w ith perennial asthma who were receiving appropriate medical treatment. (C) 1997, Massachusetts Medical Society.