ATP and Capsaicin Cough Provocation Test in Chronic Cough and Bronchiectasis

Bronchiectasis Clinical Trial

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

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT03638063
• Other study ID #: GuangzhouIRD01
• Status: Recruiting
• Start date: October 29, 2018
• Est. completion date: July 2020

Study information

• Verified date: February 2020
• Source: Guangzhou Institute of Respiratory Disease
• Contact: Wei-jie Guan, MD
• Phone: +86-13826042052
• Email: battery203[@]163.com
• Is FDA regulated: No
• Study type: Observational

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 200
• Est. completion date: July 2020
• Est. primary completion date: July 2020
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 60 Years

Eligibility

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

Related Conditions & MeSH terms

• Bronchiectasis
• Chronic Cough
• Cough

Intervention

Diagnostic Test:
• Adenosine Triphosphate
Adenosine Triphosphate aerosol
• capsaicin
capsaicin aerosol

Locations

Country	Name	City	State
China	First Affiliated Hospital of Guangzhou Medical University	Guangzhou	Guangdong

Sponsors (1)

Lead Sponsor	Collaborator
Guangzhou Institute of Respiratory Disease

Country where clinical trial is conducted

China, 

References & Publications (4)

Fowles HE, Rowland T, Wright C, Morice A. Tussive challenge with ATP and AMP: does it reveal cough hypersensitivity? Eur Respir J. 2017 Feb 8;49(2). pii: 1601452. doi: 10.1183/13993003.01452-2016. Print 2017 Feb. — View Citation

Fuller RW. Cough provocation tests: their clinical value. Pulm Pharmacol Ther. 2002;15(3):273-6. Review. — View Citation

Guan WJ, Gao YH, Xu G, Lin ZY, Tang Y, Li HM, Lin ZM, Zheng JP, Chen RC, Zhong NS. Capsaicin cough sensitivity and the association with clinical parameters in bronchiectasis. PLoS One. 2014 Nov 19;9(11):e113057. doi: 10.1371/journal.pone.0113057. eCollection 2014. — View Citation

Torrego A, Haque RA, Nguyen LT, Hew M, Carr DH, Wilson R, Chung KF. Capsaicin cough sensitivity in bronchiectasis. Thorax. 2006 Aug;61(8):706-9. Epub 2006 Apr 6. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	C5 (Provocant concentration eliciting at least 5 coughs)	Provocant concentration eliciting at least 5 coughs	18 months
Secondary	ED50 (half maximal effective Dose)	50% effective dose of provocant	18 months
Secondary	Emax (effective concentration of provocant eliciting maximal cough count)	effective concentration of provocant eliciting maximal cough count	18 months
Secondary	potency ratio	ATP/capsaicin potency ratio	18 months
Secondary	Difference in cough VAS score (a 10-point likert scale for assessing the global severity of cough, no subscale was applied)	The difference between pre- and post-challenge cough VAS scores	18 months
Secondary	The incidence of adverse events (i.e. dry throat , pharyngeal itching)	adverse events such as dry throat , pharyngeal itching, wheeze or dyspnea according to the subject's reporting to record the rate of the incidence and the severity (the aboved-mentioned VAS score would be applied)	18 months
Secondary	Cough dose ratio (CDR)	the ratio of cough count and dose/concentration	18 months