Pilot Study of Zinc Acetate for Chronic Cough

 描述(由申请人提供)：咳嗽是向初级保健医生提出的最常见的医学状况。慢性咳嗽的定义是持续时间超过八周。慢性顽固性咳嗽，即使治疗了特定的加重条件或经验性治疗，也没有反应，占新的肺部专家转诊的20%。普遍的科学共识是，这些患者患有呼吸道咳嗽感受器的过敏症。然而，少数可用的镇咳治疗方案受到不良反应、缺乏疗效和滥用潜力的限制。最近的证据已经确定了人类呼吸道的关键咳嗽受体，并发现了调节这些受体敏感性的Na-K-ATPase的特定亚型。二价阳离子锌是该酶相对特异的阻断剂，在动物模型中可降低咳嗽敏感性。在人类中，适当剂量的锌在缩短鼻病毒感染后的咳嗽持续时间方面是有效的。此外，锌作为一种营养补充剂和威尔逊氏病的治疗方法，有很强的安全性记录。因此，我们建议进行两项研究，为醋酸锌150毫克/天(Galzin(R))治疗慢性顽固性咳嗽患者的最终试验的设计和可行性提供信息。第一项研究是一项试验性随机临床试验，36名患者每天服用安慰剂或150毫克醋酸锌。这场审判将决定最终审判是否可行和非徒劳。第二项研究是对100名患者进行的一项小组研究，以确定拟议的患者报告的咳嗽结果测量的统计和心理测量特征。这些试验将由美国肺脏协会航空临床研究中心(ALA-ACRC)进行，该中心在临床试验方面有着长期成功的记录。

 DESCRIPTION (provided by applicant): Cough is the most common medical condition presenting to primary care physicians. Chronic cough is defined by persistence longer than eight weeks. Chronic refractory cough that does not respond despite treatment for specific aggravating conditions or empiric treatment accounts for up to 20% of new pulmonary specialist referrals. The general scientific consensus is that such patients suffer from hypersensitivity of the airway cough receptors. However, the few available antitussive treatment options are limited by adverse effects, lack of efficacy, and abuse potential. Recent evidence has identified the key cough receptors of the human airway and has identified the specific isoform of Na-K-ATPase that modulates the sensitivity of these receptors. The divalent cation Zinc is a relatively specifi blocker of this enzyme and decreases cough sensitivity in animal models. In humans, Zinc in adequate doses has been effective in reducing cough duration after rhinovirus infections. Further, zinc has a strong safety record as a nutritional supplement and as a treatment for Wilson's disease. Accordingly, we are proposing two studies to inform the design and feasibility of a definitive trial of zinc acetate 150 mg/day (Galzin (r)) for patients with chronic refractory cough. The first study is a pilot randomized clinical trial in 36 patients treated with either placbo or 150 mg Zinc acetate daily. This trial will determine whether a definitive trial is feasible and non-futile. The second study is a panel study of 100 patients to determine the statistical and psychometric characteristics of the proposed patient-reported cough outcome measures. The trials will be conducted by the American Lung Association Airways Clinical Research Centers (ALA-ACRC) which has a long-standing successful track record for clinical trials.