A study published in the European Annals of Allergy and Clinical Immunology demonstrated that in moderate to severe persistent seasonal allergic rhinitis patients, the clinical improvement with pre-seasonal allergoid/grass pollen immunotherapy is accompanied by a prominent rise in specific IgG4 blocking antibodies. Additionally, single-allergen immunotherapy can arouse comparable clinical effectiveness and immunological alterations in polysensitized as well as monosensitized people diagnosed with grass pollen allergy.

Investigators undertook this study to determine the efficacy of pre-seasonal immunotherapy in monosensitized and polysensitized people suffering from grass pollen allergy. The immunotherapy group consisted of 46 volunteers who were treated with grass pollen allergoid immunotherapy while the control group consisted of 28 volunteers who received conventional medical therapy. These groups were segregated into polysensitized and monosensitized groups.

All the participants were followed with symptom-medication scores, and a visual analogue scale (VAS). Utilizing the Mini Rhinoconjunctivitis Quality of Life Questionnaire (Mini-RQLQ) questionnaire, an evaluation of the quality of life was done. Prior to and following seven weeks of immunotherapy, the phleum pratense specific IgE and IgG4 estimations were carried out.

In the immunotherapy group, 15th weekly symptom-medication scores and VAS scores between May and August were reported to be considerably reduced when compared to the control group. The phleum pratense specific IgE and IgG4 levels were remarkably greater after immunotherapy in comparison with those before immunotherapy.  Additionally, the levels of phleum pratense specific IgG4 following immunotherapy were also substantially raised when compared to the control group. 

The improvements in activities-practical problems and non-nose/eye symptoms quality of life scores were remarkably distinct between the study groups. Regarding immunological and clinical parameters in monosensitized and polysensitized people, no difference was witnessed. Hence, preseasonal allergoid immunotherapy is clinically and immunologically effective in seasonal allergic rhinitis people.