Efficacy and safety of Artemisia annua pollen sublingual immunotherapy in patients with seasonal allergic rhinoconjunctivitis with or without comorbid asthma: A real-world study.

ObjectiveThis study aimed to evaluate the clinical efficacy and safety of Artemisia annua pollen allergen sublingual immunotherapy combined with symptomatic medication in patients with seasonal allergic rhinoconjunctivitis or seasonal allergic rhinoconjunctivitis with asthma.MethodsThis open-label, observational cohort study was conducted from November 2024 to May 2025 and included a total of 500 patients diagnosed with A. annua pollen-induced seasonal allergic rhinoconjunctivitis; after accounting for dropouts, 354 patients remained eligible for analyses, including 228 patients with isolated seasonal allergic rhinoconjunctivitis and 126 patients with seasonal allergic rhinoconjunctivitis and asthma. Participants received A. annua pollen sublingual immunotherapy plus standard symptomatic treatment and were followed up during the 2025 pollen season. Primary outcomes included changes in the total rhinoconjunctivitis symptom, total medication, combined symptom-medication, and visual analog scale scores from that at baseline (2024 pollen season). For patients with concomitant asthma, asthma daytime symptom and asthma nighttime symptom scores were also recorded. Efficacy was assessed by comparing scores between the two pollen seasons, and safety was evaluated based on occurrence of adverse events. This study was retrospectively registered via the National Medical Research Registration System (PID: 332836, syncing to ChiCTR); the formal registration number is pending administrative review.ResultsMean pollen concentrations during the 2024 and 2025 pollen seasons were 15.07 grains/m3 (duration: 64 days) and 15.48 grains/m3 (duration: 61 days), respectively, indicating comparable exposure levels. Compared with baseline, total rhinoconjunctivitis symptom, total medication, combined symptom-medication, and visual analog scale scores decreased significantly in both groups (isolated seasonal allergic rhinoconjunctivitis and seasonal allergic rhinoconjunctivitis with asthma groups, all p < 0.001). Among patients with comorbid asthma, asthma daytime symptom and asthma nighttime symptom scores also improved significantly (p < 0.001). Adverse events occurred in 64 patients with isolated seasonal allergic rhinoconjunctivitis and 11 patients with seasonal allergic rhinoconjunctivitis and asthma; all adverse events resolved spontaneously or with minimal intervention, and no serious adverse events were reported.ConclusionThese findings suggest that A. annua pollen sublingual immunotherapy significantly improves seasonal symptoms in seasonal allergic rhinoconjunctivitis patients, maintains lung function stability in those with concomitant controlled asthma, and demonstrates a favorable safety profile.