UNASSIGNED: This study included 30 participants allergic to birch pollen, based on birch skin prick test, specific immunoglobulin E (IgE), and positive NAC. Participants were exposed to placebo twice, followed by 2 consecutive 4-h birch airborne exposures, repeated on 2 occasions to evaluate reproducibility and priming effect. Nasal response was defined as total corrected nasal symptom score (ΔTNSS) ≥ 5 during NAC and EEC. The primary end-point was to measure TNSS during the last 2 h of first allergen exposure. TNSS was also analyzed during natural exposure.
UNASSIGNED: The dose most commonly yielding positive TNSS during NAC was 175.2 ng/200 μL. Eighteen participants experienced ΔTNSS ≥5 during the last 2 h of the first exposure, whereas 21 had positive responses at all 4 exposures. Mean ΔTNSS was 1 with placebo versus 6 with birch. Exposures were reproducible, with no observed priming effect. Airborne Bet v 1 was 25 ng/m3, while the pollen measurement was 279/m3 during pollen season. TNSS reached 5 in 67.9% of participants during peak pollen season.
UNASSIGNED: EEC outcomes were similar to those obtained with NAC and natural exposure, suggesting the usefulness of EEC in allergic rhinitis studies. The primary end-point was reached, as 60% of participants experienced nasal responses.
■这项研究包括30名对桦树花粉过敏的参与者,根据桦树皮穿刺试验,特异性免疫球蛋白E(IgE),和积极的NAC。参与者两次接触安慰剂,随后是2次连续4小时的桦树空气暴露,重复2次,以评估重现性和启动效果。鼻反应定义为NAC和EEC期间的总矫正鼻症状评分(ΔTNSS)≥5。主要终点是在首次过敏原暴露的最后2小时内测量TNSS。在自然暴露期间还分析了TNSS。
■在NAC期间最常产生阳性TNSS的剂量为175.2ng/200μL。18名参与者在第一次暴露的最后2小时内经历了ΔTNSS≥5,而21在所有4次暴露中均有阳性反应。安慰剂的平均ΔTNSS为1,桦木的平均ΔTNSS为6。暴露是可重复的,没有观察到的启动效应。机载Betv1为25ng/m3,而花粉季节的花粉测量值为279/m3。在花粉高峰季节,TNSS达到67.9%的参与者中的5。
■EEC结果与使用NAC和自然暴露获得的结果相似,提示EEC在过敏性鼻炎研究中的有用性。达到主要终点,60%的参与者经历了鼻腔反应。