Methods
The SQ tree SLIT-tablet is a fast-dissolving pharmaceutical formulation (oral lyophilisate) for daily at-home self-administration apart from the first tablet, that must be administered at the clinic. It contains standardised allergen extract from white birch pollen (Betula verrucosa ).

Trial design

Safety data were pooled from two phase-II and one pivotal phase-III double-blinded, randomized placebo-controlled, parallel-group trials including adults and adolescents with moderate to severe allergic rhinitis and/or conjunctivitis induced by pollen from the birch homologous group. The data included subjects who received placebo or a daily dose of 12 SQ-Bet. The trials were conducted at 124 sites in total in Canada, Czech Republic, Denmark, France, Germany, Finland, Lithuania, the Netherlands, Norway, Poland, Russia and Sweden.
The subjects were treated before and during one pollen season with once-daily SQ tree SLIT-tablet or placebo administered at home. The first dose was administered under medical supervision for 30 minutes after tablet intake to assess tolerability and allow for possible treatment of any immediate side effects. The design as well as efficacy and safety results of the phase II trials and the pivotal phase-III trial have been described separately elsewhere13-15.