A phase 3 trial assessing the efficacy and safety of grass allergy immunotherapy tablet in subjects with grass pollen-induced allergic rhinitis with or without conjunctivitis, with or without asthma.

BACKGROUND: Design and execution of immunotherapy trials for seasonal allergies may be complicated by numerous factors including variable allergy testing methods, pollen levels, and timing and intensity of other seasonal allergens. We evaluated grass allergy immunotherapy tablet (AIT) treatment in North American adults with grass pollen-induced allergic rhinitis with or without conjunctivitis (AR/C), with/without asthma. METHODS: Subjects age 18-65 with clinical history of grass pollen-induced AR/C, with/without asthma were randomized 1:1 to once-daily 2800 BAU Timothy grass AIT (oral lyophilisate, Phleum pratense, 75,000 SQ-T, containing approximately 15 µg of Phl p 5) or placebo. The AR/C symptom and medication scores were recorded daily. The primary end point was the average AR/C daily symptom score (DSS) during the entire grass pollen season (GPS). Ranked key secondary end points were Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) score, daily medication score (DMS), and percentage of well days, all over entire GPS. Safety was monitored through adverse event reporting. RESULTS: Efficacy analysis included 289 subjects. Over the entire GPS, mean DSS was 6% lower with AIT versus placebo (5.69 vs. 6.06), but this difference was not statistically significant (p = 0.3475) despite significantly higher immunological response in the grass AIT group. No significant between-group differences were seen for key secondary end points. In general, DSS was high before GPS began and no clear relationship between DSS and grass pollen counts was seen during GPS. In post hoc analysis of subjects with pre-seasonal DSS ≤3, mean DSS and DMS were both significantly lower with grass AIT versus placebo (27%; p = 0.0327 and 68%; p = 0.0060, respectively). In this subgroup a relationship between DSS and grass pollen counts was observed. Grass AIT was generally well tolerated, with no events of anaphylactic shock or respiratory compromise. CONCLUSIONS: In this trial, 2800 BAU grass AIT did not demonstrate significant symptom improvement versus placebo. Lack of relationship between pollen count and symptom score in the study population, and post hoc findings among subjects with low pre-seasonal symptoms, suggest that the symptoms reported in this study were not primarily reflective of the effects of grass pollen exposure. TRIAL REGISTRATION: NCT00421655.

Randomized controlled trial of ragweed allergy immunotherapy tablet efficacy and safety in North American adults.

BACKGROUND: Ragweed is an important cause of allergic rhinitis with or without conjunctivitis (AR/C) in North America and elsewhere. Allergen immunotherapy enabling safe patient self-administration is considered an unmet clinical need. Allergy immunotherapy tablet (AIT) treatment has shown promising efficacy and safety for grass allergy but has not been assessed for ragweed allergy. OBJECTIVE: To evaluate efficacy and safety of 2 short ragweed AIT doses in patients with AR/C. METHODS: Adults with ragweed pollen-induced AR/C were randomized 1:1:1 to daily ragweed AIT (6 or 12 Amb a 1 units) or placebo before, throughout, and after ragweed season (approximately 52 weeks). Patients could use predefined allergy rescue medications in season. Efficacy end points included peak and entire season total combined score (TCS) and its components daily symptom score (DSS), and daily medication score (DMS). Safety assessments included adverse events. RESULTS: A total of 565 patients were randomized. During peak season, the 6- and 12-Amb a 1 unit ragweed AIT doses showed 21% (-1.76 score) and 27% (-2.24 score) improvement in TCS vs placebo (P < .05). The 6- and 12-Amb a 1 unit AIT doses significantly improved DSS and DMS vs placebo (P < .05). Peak and entire season efficacy were comparable. The 12-Amb a 1 unit AIT dose reduced peak-season TCS vs placebo by 21% and 25% in subgroups with and without local application-site reactions, respectively. Most treatment-related adverse events were mild, oral reactions; no systemic allergic reactions were reported. One patient in the 6-Amb a 1 unit group received epinephrine at an emergency facility for sensation of localized pharyngeal edema. CONCLUSION: In this trial, ragweed AIT was effective and well tolerated in ragweed-allergic North American adults. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00783198.