Day J H, Briscoe M P, Welsh A, Smith J N, Clark A, Ellis A K, Mason J
Division of Allergy, Kingston General Hospital, Ontario, Canada.
Ann Allergy Asthma Immunol. 1997 Dec;79(6):533-40. doi: 10.1016/S1081-1206(10)63062-1.
Fexofenadine hydrochloride is the active acid metabolite of terfenadine. Fexofenadine's anti-allergic properties require confirmation in a clinical setting.
The purpose of this study was to characterize the time to onset of clinically important relief of symptoms of allergic rhinitis in subjects taking single doses of either 60 mg or 120 mg fexofenadine HCl, or placebo, after exposure to ragweed pollen in a controlled environment. Other objectives were to assess the efficacy and safety of single doses of fexofenadine HCl.
One hundred forty-six ragweed-sensitive subjects were primed in the off-season with ragweed pollen in the environmental exposure unit. One hundred thirty-six subjects who adequately responded to priming entered a single-dose placebo phase. Placebo-responders were disqualified from the study, leaving 99 subjects with adequate symptoms to be randomized and given a single dose of either fexofenadine HCl 120 mg (33), 60 mg (33) or placebo (33), after 60 minutes of allergen exposure. Exposure continued over five hours and subjects recorded symptoms every 20 minutes. This study was of a randomized, placebo-controlled, double-blind, parallel design.
Median time to onset for relaxed criteria clinically important relief was 60 minutes for both fexofenadine treatment groups, and 100 minutes for placebo (P = .018). The proportion with relief was 82% at 60 mg, 85% at 120 mg, and 64% for placebo. Treated groups had reductions in symptom scores double that of placebo.
Fexofenadine is safe and efficacious at single doses of 60 mg and 120 mg. Average time to onset was 60 minutes using controlled pollen exposure in an environmental exposure unit.
盐酸非索非那定是特非那定的活性酸代谢产物。非索非那定的抗过敏特性需要在临床环境中得到证实。
本研究的目的是确定在受控环境中接触豚草花粉后，服用单剂量60毫克或120毫克盐酸非索非那定或安慰剂的受试者出现过敏性鼻炎临床重要症状缓解的起效时间。其他目的是评估单剂量盐酸非索非那定的疗效和安全性。
146名对豚草敏感的受试者在非过敏季节于环境暴露单元中用豚草花粉进行致敏。136名对致敏有充分反应的受试者进入单剂量安慰剂阶段。对安慰剂有反应的受试者被排除在研究之外，剩下99名有足够症状的受试者被随机分组，并在接触过敏原60分钟后给予单剂量120毫克（33名）、60毫克（33名）盐酸非索非那定或安慰剂（33名）。暴露持续5小时，受试者每20分钟记录一次症状。本研究采用随机、安慰剂对照、双盲、平行设计。
对于临床重要缓解的宽松标准，两个非索非那定治疗组的中位起效时间均为60分钟，安慰剂组为100分钟（P = 0.018）。60毫克组缓解比例为82%，120毫克组为85%，安慰剂组为64%。治疗组的症状评分降低幅度是安慰剂组的两倍。
60毫克和120毫克单剂量的非索非那定安全有效。在环境暴露单元中使用受控花粉暴露时，平均起效时间为60分钟。
