Sublingual immunotherapy in daily medical practice: effectiveness of different treatment schedules - IPD meta-analysis

To compare the effectiveness of perennial and co-seasonal high-dose sublingual immunotherapy (SLIT) treatments as well as ultra-rush and classical titrations in a real-world setting for pollen allergens. An individual patient data (IPD) meta-analysis was performed of three open, prospective observational studies on high-dose SLIT using IR-standardised allergen extracts in patients with allergic rhinitis with and without asthma. In total, 1052 patients aged 24.9 years (mean) were treated with SLIT and included in this IPD meta-analysis. Individual studies and total data pool analyses revealed consistent improvements in rhinoconjunctivitis symptom scores. Stratified analyses revealed consistent improvements in symptomatic score and medication score regardless of the type of sensitisation and type of treatment. Ultra-rush titration resulted in considerably more pronounced improvement in symptom scores than classical titration, possibly due to better compliance of patients receiving that supervised titration. Adverse events occurred in 24% of patients during titration and in 18% of patients during maintenance treatment. The vast majority of events (89% and 87%) were mild-to-moderate, predominantly local symptoms in the oral cavity. There were no differences detected between the study titration or treatment schedules. No serious adverse reactions were reported. Nearly all patients (88%) decided to continue SLIT after completion of the studies. High-dose SLIT with seasonal allergens given as co-seasonal or perennial treatment appears to be effective and well-tolerated in daily medical practice. Improved compliance under ultra-rush titration and seasonal SLIT treatment may further enhance effectiveness. Randomised controlled trials are requested for the further evaluation of these findings.