Safety and effectiveness of a 300 IR house dust mite sublingual tablet: descriptive 4-year final analysis of a post-marketing surveillance in Japan.

Background: Data are limited for clinical outcomes with house dust mite (HDM) allergen immunotherapy beyond 2 years' observation. Materials & methods: A post-marketing drug-use survey assessed the safety and effectiveness of the 300 index of reactivity (IR) HDM tablet during use for up to 4 years in Japan. Results: 538 patients were evaluable for safety and 383 for effectiveness. Most adverse drug reactions (ADRs) occurred early and were local reactions; 5.6% of 249 total events were reported during years 2 to 4 as new ADRs after the interim analysis. The CAP-RAST score was identified as a potential risk factor for ADRs. The proportion of evaluable patients with severe allergic rhinitis symptoms decreased from 46.4% at baseline (n = 317) to 1.0% at 4 years (n = 104). Patients (n = 16) who discontinued 300 IR HDM tablet due to symptomatic improvement had sustained improvement relative to baseline 1 to 2 years later. Conclusion: Long-term use of the 300 IR HDM tablet is safe and effective.

The 300 index of reactivity house dust mite (HDM) sublingual tablet (Actair^®) is a treatment option for people with HDM allergy. A Japanese study investigated the safety and effectiveness of the HDM sublingual tablet during its use for up to 4 years. Less than a third of patients (29%) reported adverse effects, mainly itching or irritation in the mouth. The percentage of patients with no allergic rhinitis symptoms increased from 0.3% before treatment to 57.7% after 4 years of use. The percentage of patients who perceived that their allergic rhinitis had improved 'substantially' compared with before treatment increased from 22.3% at 6 months to 73.5% at 4 years. Patients who ended treatment with the HDM sublingual tablet because their symptoms had improved continued to perceive benefit 1 to 2 years later. Clinical Trial Registration: University hospital Medical Information Network (UMIN) Clinical Trials Registry identifier: UMIN000042840.

Safety and effectiveness of the 300 IR sublingual house dust mite allergen immunotherapy tablet: 2-year interim analysis of a specified drug-use survey.

Background: The efficacy and safety of a house dust mite sublingual tablet (HDM-tab) have been demonstrated in clinical trials, but the findings must be confirmed in real-world use among more widespread patient populations. Materials & methods: A postmarketing drug-use survey is assessing the drug's safety and effectiveness during routine use for up to 4 years. This 2-year interim analysis reports data collected up to March 2020. Results: Of 545 registered outpatients, 526 were evaluable for safety and 371 for effectiveness. Most common adverse drug reactions were local reactions. Mean rhinitis severity score decreased from 2.5 ± 0.8 at baseline to 1.4 ± 0.9, 1.1 ± 0.8 and 1.0 ± 0.8 at 6 months, 1 year and 2 years, respectively. Conclusion: The HDM tab appears to be safe and effective in real-world conditions during 2 years of continuous use. Trial registration number: University hospital Medical Information Network (UMIN) Clinical Trials Registry identifier: UMIN000042840.