Timothy grass sublingual immunotherapy (SLIT) tablets are indicated for children with allergic rhinitis with or without conjunctivitis.

To use pooled analyses to assess the short- and long-term tolerability and safety of timothy grass SLIT-tablet in children.

Data from 9 double-blinded, randomized European or North American trials that included children with allergic rhinitis with or without conjunctivitis treated up to 3 years with once-daily timothy grass SLIT-tablet or placebo were pooled.

In all, 1818 (timothy grass SLIT-tablet, n = 923; placebo, n = 895) subjects were included in the analysis. The frequency of treatment-emergent adverse events (AEs) was 86% in the SLIT-tablet group and 83% in the placebo group, and the frequency of treatment-related AEs (TRAEs) was 59% and 23%, respectively. Most (98%) TRAEs were mild to moderate in severity. The 2 most common TRAEs with SLIT-tablet were oral pruritus (33%) and throat irritation (19%), which had a median onset of 1 day and recurrence of 14.5 and 5 days, respectively. In all, 8% of subjects in the SLIT-tablet group and 2% in the placebo group discontinued because of AEs. There were 7 serious AEs assessed as related to SLIT-tablet, 1 systemic allergic reaction (severe with a drop in blood pressure), 3 epinephrine administrations, no eosinophilic esophagitis events, and no serious airway obstructions. The safety profile was similar in subjects across geographic regions and with and without asthma.

Pooled data indicate that short- and long-term timothy grass SLIT-tablet is well tolerated in children, regardless of geographic region. AEs were generally local, mild, and transient allergic reactions.