Effect of Oral Procaterol on Postinfectious Persistent Cough

Study Overview
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Brief Summary
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The purpose of this study is to investigate the effectiveness of oral procaterol in treatment of non-asthmatic patients who suffer from persistent cough following upper respiratory tract infection (URTI).

Detailed Description
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Persistent cough following upper respiratory tract infection (URTI) is a common problem in the clinical practice, namely post-infectious cough. The potential mechanisms are viral-induced airway epithelial damage that leads to 1) airway hyperresponsiveness and airway narrowing, 2) increase in vascular permeability resulting in airway edema, and 3) activation of inflammatory mediators from inflammatory cells resulting in airway smooth muscle contraction. It is usually spontaneously resolved, although various therapeutic trials have been used with unpredictable results. Regarding to bronchodilators, inhaled ipratropium was effective in reducing cough symptom in a small study (N=14). We conduct a double-blind randomized placebo-controlled trial to investigate the effectiveness of oral procaterol, as a bronchodilator, in non-asthmatic adult patients suffering from persistent cough post URTI. Eligible patients who have cough lasting longer than 3 weeks post URTI with normal spirometry will be randomized to receive either placebo or procaterol (25 microgram twice daily) for 4 weeks. The primary outcome is cough symptom score using Leicester cough questionnaire (LCQ). The secondary outcomes are pulmonary function tests (spirometry, impulse oscillometry) and exhaled nitric oxide and quality of life (SF-36). All outcomes are measured at baseline, 2 weeks, and 4 weeks. Bronchoprovocation test with methacholine is performed at baseline and 4 weeks to determine the provocative concentration of methacholine that induces falling of FEV1 >or =20%. Adverse events will be recorded every visit. Data analysis will be in both intention-to-treat and per-protocol fashion. A linear mixed-effect regression model will be applied to assess treatment effect on LCQ score, SF-36, and lung function. Within-subject variation will be fitted in the model as random effects whereas the treatment will be considered as a fixed effect. Time at measurement (i.e., 2- and 4-week) will also be included in the mixed model by treating it as fixed-effect. Marginal treatment effects between treatments and time will be then estimated and compared.

Official Title
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Effect of Oral Procaterol on Chronic Persistent Cough Following Upper Respiratory Tract Infection: Double-Blind Randomized Placebo-Controlled Trial

Conditions
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Cough

Intervention / Treatment
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* Drug: Procaterol
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Having persistent cough that lasts longer than 3 weeks following URTI Currently being a non-smoker Having normal spirometry (FEV1>or= 80% predicted) Obtain consent form Exclusion Criteria: Having cough more than 8 weeks Having history of allergic or intolerance to β2 agonist Having diagnosis of asthma by physicians Presence of wheeze or rhonchi on physical examination Having radiographic evidence of pneumonia, tuberculosis or sinusitis Having significant gastroesophageal reflux symptoms suggested by GERD-Q questionnaire (GERD-Q score > 8) Currently taking ACE-inhibitor Being active smokers Refuse to participate in the study

Ages Eligible for Study
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Minimum Age: 15 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Procaterol<br>Procaterol 25 micrograms/tablet, 1 tablet twice daily for 4 weeks | Drug: Procaterol<br>* Procaterol 25 micrograms/tablet, 1 tablet twice daily for 4 weeks<br>* Other names: procaterol hydrochloride;|
| Placebo Comparator: Placebo<br>Placebo twice daily for 4 weeks | Drug: Placebo<br>* Placebo twice daily for 4 weeks<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total score from Leicester cough questionnaire |  | up to 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quality of life score from SF-36 |  | 2 weeks and 4 weeks | 
| Spirometric parameters (FEV1, Forced expiratory flow between 25% and 75% of vital capacity; FEF25-75%) |  | 2 weeks and 4 weeks | 
| Impulse oscillometry parameters (airway resistance at 5 Hz, and 20 Hz, difference of airway resistance at 5 Hz and 20 Hz) |  | 2 weeks and 4 weeks | 
| Provocative concentration of methacholine that induces falling of FEV1 > or= 20% (PC20) |  | 4 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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postinfectious cough, postviral cough