Once-daily administration of a grass allergy immunotherapy tablet (AIT) preseasonally and during the grass pollen season (GPS) is clinically effective, well-tolerated, and may be a new therapeutic modality for children with grass pollen allergy, according to data presented at the annual meeting of the American Academy of Allergy, Asthma and Immunology in New Orleans. Researchers at the University of Tennessee Health Science Center in Memphis, and colleagues, conducted the research. It builds on a European sublingual immunotherapy trial with grass AIT that showed efficacy and tolerability in children with allergic rhinoconjunctivitis (ARC). The American researchers undertook a phase III trial of daily administration of SQ-standardized grass AIT (oral lyophilisate of Phleum pratense (Timothy grass) in a North American grass-allergic pediatric population. They randomized 345 children (ages 5-17 years) with grass pollen ARC on a 1:1 ratio to once-daily treatment with grass AIT or placebo for over eight weeks prior to and throughout the 2009 GPS. Rescue medications and symptoms were recorded in daily e-diaries daily; efficacy was measured during the GPS. The primary efficacy endpoint comprised the total combined daily symptom score (DSS) and daily medication score (DMS). Secondary endpoints were individual DSS, DMS, and the Juniper (pediatric or adolescent) rhinoconjunctivitis quality of life questionnaire (RQLQ). Immunological endpoints included specific IgG4 and IgE-blocking factor. Safety was assessed by adverse events (AEs). Following data analysis, the researchers found that 89% of the subjects had been multisensitized. The AIT group had a statistically significant improvement (26%, P=0.001) in total combined score compared with the placebo group. The DSS (25%, P=0.002), DMS (32%, P=0.066), and RQLQ (mean difference 0.32 (18%, P=0.028) also improved for the active group. Regarding AEs, the majority of treatment-related ones were application site reactions, with no reports of anaphylactic shock. According to the researchers, the study was the first successful phase III trial of grass AIT in children in North America.