Trial of Grazax (sublingual allergy immunotherapy tablet) shows benefits in allergy prevention-ALK

ALK has announced top-line results from the Grazax (sublingual allergy immunotherapy tablet) Asthma Prevention (GAP) trial with ALK’s allergy immunotherapy tablet against grass pollen allergy. The GAP trial consisted of a three-year treatment phase and a two-year follow-up phase and included 812 children aged 5–12 years at the start of the treatment phase. The primary objective was to investigate the effect of Grazax compared with placebo on the risk of developing asthma. The primary endpoint of the trial was time to first diagnosis of reversible impairment of lung function.

Within the five year evaluation period there was no detectable effect in terms of time to the first diagnosis of reversible impairment of lung function and hence the primary endpoint of the trial was not met. In contrast, treatment with Grazax had a positive effect on the children’s asthma symptoms and use of asthma medication. The odds ratio (secondary endpoint) for experiencing asthma symptoms or using asthma medication, at the end of the five-year evaluation period, was 0.66 in favour of Grazax treatment. Moreover, the proportion of patients experiencing asthma symptoms or using asthma medication was significantly reduced from year 2 and onwards in the group receiving Grazax treatment compared with the placebo group (with relative risk reductions ranging from 36-50%). The beneficial effect on asthma symptoms and asthma medication use was observed year-round in the two-year follow-up phase.

In addition, the GAP trial demonstrated efficacy on grass allergic rhinoconjunctivitis in the three treatment years and in two follow-up years, showing a 23-30% symptom reduction in patients receiving Grazax treatment compared with those receiving placebo (secondary endpoint). The level of symptom reduction was in line with previous trial results. All patients had access to symptom-relieving rhinoconjunctivitis medications throughout the five years of the trial. At the end of the trial, the use of this medication was recorded and patients who received Grazax treatment also used significantly less rhinoconjunctivitis medications compared with those receiving placebo.