Clinical efficacy in one-year treatment with Artemisia annua-SLIT drops in monosensitized and polysensitized individuals

Seasonal allergic rhinoconjunctivitis (SARC) caused by Artemisia seriously affects patients' quality of life in northern China. This study aimed to estimate further the efficacy and safety of a one-year course of Artemisia annua-sublingual immunotherapy (SLIT) on SARC patients.This was an open-label, randomized, controlled, single-centre study involving 150 SARC patients induced by Artemisia, randomized to SLIT group (n = 75, SLIT along with pharmacotherapy) or control group (n = 75, pharmacotherapy only). According to the skin prick test (SPT) results, the SLIT group was divided into monosensitized and polysensitized groups to analyze the influence of sensitization status on the efficacy of Artemisia annua-SLIT. The clinical indicators of this study were total rhinoconjunctivitis symptom score (TRSS), total medication score (TMS), combined scores of medication and rhinoconjunctivitis symptom (CSMRS), and score of visual analog scale (VAS). Safety was evaluated by the occurrence of adverse events (AEs). Daily administration of the drops was recorded in diaries by the patients.After nearly one year of treatment and follow-ups, there was a significant decline in TRSS, TMS, CSMRS, and VAS from the baseline scores in the SLIT group (p < 0.001). However, as pollen counts increased in 2022, indicators above in the control group increased significantly during the peak pollen phase (PPP) in 2022 grass pollen season (GPS) compared to the baseline. Meanwhile, we found no significant difference in TRSS, TMS, CSMRS, and VAS between the monosensitized and polysensitized groups (p > 0.05). Moreover, the result indicated that the clinical improvement in TRSS, TMS, CSMRS, and VAS was still observed in polysensitized patients who were allergic to Artemisia pollen and sensitized to house dust mite (HDM) (n = 15) in PPP of 2022, compared to the baseline value (p < 0.001).Artemisia annua-SLIT was proven effective, tolerable and safe in patients with SARC after nearly one year of treatment, whether monosensitization or polysensitization.