Ramsdell J W, Colice G L, Ekholm B P, Klinger N M
Department of Medicine, University of California, San Diego, Medical Center, USA.
Ann Allergy Asthma Immunol. 1998 Dec;81(6):593-9. doi: 10.1016/S1081-1206(10)62711-1.
As a result of the pending ban on chlorofluorocarbon production, the non-chlorofluorocarbon propellant 1,1,1,2-tetrafluoroethane (HFA-134a) is being evaluated as a replacement for CFCs in metered-dose inhalers.
This cumulative dose response study compared the safety and bronchodilator efficacy of 16 cumulative inhalations of albuterol sulfate in an HFA-134a, CFC-free propellant system (108 microg of albuterol sulfate, equivalent to 90 microg of albuterol base) with that of equivalent doses of albuterol in a conventional CFC propellant system.
Twenty-two patients with at least a 12-month history of stable asthma, who were currently taken an inhaled beta-adrenergic bronchodilator, and who had a FEV1 between 40% and 80% of predicted, were enrolled in this randomized, modified-blind, two-period crossover study. One, 1, 2, 4, and 8 inhalations of study drug were self-administered at 30-minute intervals, resulting in 16 cumulative inhalations. Pulmonary function and safety measures were assessed after each dosing interval.
A significant dose response was found for HFA-134a albuterol sulfate and CFC albuterol with regard to changes in FEV1, serum potassium, heart rate, and blood pressure after 16 cumulative inhalations. No significant differences were demonstrated between HFA-134a albuterol sulfate and CFC albuterol for any FEV1 or safety parameter at any cumulative dose level. No clinically meaningful laboratory or physical examination abnormalities were found with administration of either HFA-134a albuterol sulfate or CFC albuterol.
HFA-134a albuterol sulfate provides bronchodilation comparable to CFC albuterol and has a similar safety profile.
由于即将禁止生产氯氟烃，正在评估非氯氟烃推进剂1,1,1,2 - 四氟乙烷（HFA - 134a）作为定量吸入器中氯氟烃替代品的可行性。
本累积剂量反应研究比较了在不含氯氟烃的HFA - 134a推进剂系统中16次累积吸入硫酸沙丁胺醇（108微克硫酸沙丁胺醇，相当于90微克沙丁胺醇碱）与在传统氯氟烃推进剂系统中同等剂量沙丁胺醇的安全性和支气管扩张疗效。
22名患有至少12个月稳定哮喘病史、目前正在使用吸入型β - 肾上腺素能支气管扩张剂且第一秒用力呼气量（FEV1）在预测值的40%至80%之间的患者参与了这项随机、改良盲法、两阶段交叉研究。研究药物以30分钟的间隔进行1、1、2、4和8次吸入，共进行16次累积吸入。在每个给药间隔后评估肺功能和安全指标。
在16次累积吸入后，就FEV1、血清钾、心率和血压的变化而言，发现HFA - 134a硫酸沙丁胺醇和氯氟烃沙丁胺醇有显著的剂量反应。在任何累积剂量水平下，HFA - 134a硫酸沙丁胺醇和氯氟烃沙丁胺醇在任何FEV1或安全参数方面均未显示出显著差异。使用HFA - 134a硫酸沙丁胺醇或氯氟烃沙丁胺醇均未发现具有临床意义的实验室或体格检查异常。
HFA - 134a硫酸沙丁胺醇提供的支气管扩张效果与氯氟烃沙丁胺醇相当，且安全性相似。
