Brief Title
ATP and Capsaicin Cough Provocation Test in Chronic Cough and Bronchiectasis
Official Title
Adenosine Triphosphate and Capsaicin Cough Provocation Test for Identifing Patients With Chronic Cough Who Have Differential Responses to Purinergic Receptor Antagonists: a Randomized, Cross-over, Single-blind Trial
Brief Summary
This is a randomized, cross-over, single-blind trial. Eligible patients will be randomly
assigned to undergo either capsaicin or adenosine triphosphate (ATP) cough provocation test,
followed by a washout period of 2 to 14 days. Participants will be crossed-over to undergo
another cough provocation test. Patient would be under observation in the out-patient clinics
for ~2 hours following the cough provocation tests in case of severe adverse events.
Detailed Description
This is a randomized, cross-over, single-blind trial. After verification of the entry
criteria, eligible patients will be, based on the randomization codes, randomly assigned to
undergo either capsaicin or ATP cough provocation test (the participants will inhale
capasaicin or ATP incremental concentration to induce cough, meanwhile the number of coughs
and adverse events will be recorded in each concentration during the first 30 seconds),
followed by a washout period of 2 to 14 days (no major changes in the use of concomitant
medications are allowed,especially the medcines which are not allowed before test ).
Participants will be crossed-over to undergo another cough provocation test. Patient would be
under observation in the out-patient clinics for ~2 hours following the cough provocation
tests in case of severe adverse events. Twenty four hours after each test, a follow-up
telephone visit will be scheduled for all patients to record any response which may be
related to the test.
Study Type
Observational
Primary Outcome
C5 (Provocant concentration eliciting at least 5 coughs)
Secondary Outcome
ED50 (half maximal effective Dose)
Condition
Chronic Cough
Intervention
Adenosine Triphosphate
Study Arms / Comparison Groups
Chronic cough
Description: patients with chronic cough who remain clinically stable
Publications
* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.
Recruitment Information
Recruitment Status
Diagnostic Test
Estimated Enrollment
200
Start Date
October 29, 2018
Completion Date
July 2020
Primary Completion Date
July 2020
Eligibility Criteria
Inclusion Criteria:
- Out-patients of either gender, ex- or never-smokers, aged between 18 and 60 years
- Cough symptoms lasting for more than 8 weeks
- Remaining free of acute upper respiratory tract infection for at least 4 weeks
- Agreed to participate in the trial and signed informed consent.
Exclusion Criteria:
- Patients with serious systemic diseases (such as malignant tumors), bullae, severe
uncontrolled asthma, and a history of major hemoptysis
- Systemic antibiotic use (except for maintenance low-dose macrolides) within 4 weeks
- Pregnancy or lactation
- Any known history of sensitivity to ATP or capsaicin
- Poor understanding of the test procedure
- Diagnosed with cough variant asthma or Eosinophilic bronchitis
Gender
All
Ages
18 Years - 60 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Contacts
Ke-fang Lai, MD, +86-13826042052, [email protected]
Location Countries
China
Location Countries
China
Administrative Informations
NCT ID
NCT03638063
Organization ID
GuangzhouIRD01
Responsible Party
Principal Investigator
Study Sponsor
Guangzhou Institute of Respiratory Disease
Study Sponsor
Ke-fang Lai, MD, Study Chair, Guangzhou Institute of Respiratory Health Locations: China, Guangdong First Affiliated Hospital of Guangzhou Medical
Verification Date
February 2020