The Effect of Beta-2 Adrenergic Polymorphisms on the Bronchoprotective Effects of Regular Salmeterol Treatment in Asthma
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 30
- 试验地点
- 2
- 主要终点
- Comparison of the Maximum Percent Fall in FEV1 After Exercise Challenge at the End of the 2-week Treatment Period Between Arg/Arg and Gly/Gly Patients
研究概览
简要总结
The purpose of the study is to find out how well a long-acting beta agonist like salmeterol works in people with different forms of the same gene. Our hypothesis is that asthmatics with the Arg/Arg genotype will have loss of bronchoprotection against exercise-induced asthma with regular salmeterol treatment, as compared to asthmatics with the Gly/Gly genotype.
详细描述
In many patients with asthma, exercise-induced bronchoconstriction is a common and oftentimes limiting characteristic. Inhaled β2-adrenoreceptor agonists like albuterol are the most effective treatments available for the relief of acute asthma symptoms. However, there is evidence that regular use may lead to adverse effects in some patients. Previous studies have shown that polymorphisms of the β2-adrenergic receptor can influence airway responses to regular inhaled beta-agonist treatment.
Pharmacogenetics is the study of how genetic differences influence the variability in patients' responses to therapy, both therapeutic and adverse. Genetic susceptibility and environmental factors both play major roles in the etiology of asthma. The strong familial clustering of asthma has lead to a surge of research into the genetic predisposition of asthma. The aim of the present study is to utilize a double-blinded prospective cohort study to investigate whether genotype-specific effects occur when assessing the duration of protection conferred against exercise-induced bronchoconstriction by regular salmeterol treatment.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 18 Years 至 50 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Both male and female
- •18 to 50 years of age
- •Resting FEV1 ≥ 65% of predicted normal
- •Exercise-induced bronchoconstriction defined as a decrease in FEV1 of ≥ 20% following a standardized exercise challenge when compared to pre-exercise baseline FEV1 value measured 5 minutes before exercise
- •Must be Arg/Arg or Gly/Gly genotype
排除标准
- •Long-acting beta agonist use within 12 weeks of the first exercise challenge
- •Smoking within past 12 months
- •Greater than 10-pack years smoking history
- •Unresolved signs and/or symptoms of an upper respiratory tract infection within 4 weeks of first exercise challenge
- •Asthma exacerbation within 4 weeks of first exercise challenge requiring change in type, dose or frequency of medications and/or an unscheduled visit to an health care provider, including emergency room or hospital
- •Subject has exercised or performed strenuous activity within 72 hours of the first exercise challenge
- •Subject has been exposed to cold air sufficient to provoke symptoms of bronchospasm within 2 hours of exercise challenge
- •In addition to asthma, the subject has an active, acute or chronic pulmonary disorder documented by history, physical examination, or chest x-ray
- •Subject has evidence of ischemic, valvular, hypertrophic, familial or other forms of heart disease that would put the subject at risk during exercise testing or that would interfere with the ability to achieve protocol-specified heart rates during exercise testing
- •Subject has used systemic corticosteroids within 1 month of first exercise challenge
研究组 & 干预措施
Gly/Gly
Gly/Gly subjects on 2 week salmeterol treatment
干预措施: salmeterol (Drug)
Arg/Arg
Arg/Arg subjects on 2 week salmeterol treatment
干预措施: salmeterol (Drug)
结局指标
主要结局
Comparison of the Maximum Percent Fall in FEV1 After Exercise Challenge at the End of the 2-week Treatment Period Between Arg/Arg and Gly/Gly Patients
时间窗: 2 weeks after exercise challenge
次要结局
- Comparison of the Maximum Percent Fall in FEV1 From Pre-salmeterol Baseline to the End of the 2-week Treatment Period Between Arg/Arg and Gly/Gly Patients(2 weeks from pre-salmeterol baseline)
- Comparison of the Maximum Percent Fall in FEV1 After 1st Dose of Salmeterol to the End of the 2-week Treatment Period Between Arg/Arg and Gly/Gly Subjects(2 weeks after 1st dose of Salmeterol)
研究者
Elliot Israel, MD
Director, Asthma Research Center
Brigham and Women's Hospital