Efficacy and safety of the SQ-standardized grass allergy immunotherapy tablet in mono- and polysensitized subjects

The efficacy of single-allergen-specific immunotherapy in polysensitized subjects is a matter of debate. We therefore performed a post hoc analysis of pooled data from six randomized, double-blind, placebo-controlled trials (N = 1871) comparing the efficacy and safety of the SQ-standardized grass allergy immunotherapy tablet (AIT), Grazax (Phleum pratense 75 000 SQ-T/2800 BAU, ALK, Denmark), in mono- and polysensitized subjects. A statistically significant reduction in the mean total combined symptom/medication score (TCS) of 27% was demonstrated in actively treated subjects compared with placebo (P < 0.0001). This was not dependent on sensitization status (P = 0.5772), suggesting a similar treatment effect in mono- and polysensitized subjects (i.e. reductions of the TCSs of 28% and 26%, respectively, both P < 0.0001). Finally, a comparable and favourable safety profile of grass AIT was demonstrated in the two subgroups. Thus, no difference in efficacy and safety of single-allergen grass AIT was observed between mono- and polysensitized subjects.