Evaluation of Pollinex Quattro (PQ) Grass allergen-specific immunotherapy induced immunomodulatory mechanisms for treating seasonal allergic rhinitis

A recent study found that Pollinex Quattro (PQ) Grass exhibited a superior extended regimen with a mechanistic efficacy profile compared to the conventional PQ regimen. This study was published in the journal, Clinical and Experimental Allergy.

This study included 119 subjects suffering from grass pollen seasonal allergic rhinitis (SAR) who were randomized in a 2:2:1:1 ratio. These patients received a cumulative dose of PQ Grass either as an extended pre-seasonal or conventional regimen, placebo, or placebo with MicroCrystalline Tyrosine. An exploratory endpoint, gene expression analysis, was assessed in a subgroup of 30 individuals chosen at random from each of the four treatment arms. Baseline samples and those obtained before the start and end of the grass pollen season were analyzed.

At the end of the study, transcriptome analysis showed most significant changes in the gene expression for the main Th1 candidate molecules (IL-12A, IFNγ) upregulated as well as the Th2 signature cytokines downregulated (IL-4, IL-13, IL-9). Based on the absolute value of the activation z-score, the canonical pathways analysis showed that Th1, Th2, Th17, and IL-17 were the most significantly enriched pathways. Pronounced inhibition of pro-inflammatory allergic molecules, IgE, IL-17A, IL-17F, IL-25 and activation of pro-tolerogenic molecules, IL-12A, IL-27, IL-35 was shown by upstream regulator analysis.

Based on the above results, it can be concluded that peripheral blood mononuclear cells showed an inhibition of pro-inflammatory allergic responses (Th2, Th17) while exhibiting an immune deviation towards Th1 responses. Thus, PQ Grass extended regimen may show a superior mechanistic efficacy profile compared to the conventional PQ regimen.