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Clinical Trials

Chronic Refractory Cough Cohort (COCO)




Multi-Center Trial


The American Lung Association Airways Clinical Research Center (ACRC) network is evaluating measurements of cough symptoms and the impact of cough on quality of life for people with chronic cough. A chronic cough is a cough that lasts at least 8 weeks, but often much longer. Chronic cough is common, affecting 9-12% of the population. It can have a negative impact on quality of life and may lead to social isolation, lack of sleep, and chronic fatigue. Some people find that their chronic cough gets better when they take medicines for asthma, gastroesophageal reflux (GERD), or sinus problems. However, some people are not helped by these or other medicines. People with a cough that does not respond to treatments is said to have chronic refractory cough. The Chronic Refractory Cough Cohort (COCO) study is being done to evaluate different measures of cough, including its effect on quality of life. The measures include a daily cough assessment, or cough diary, and questionnaires. COCO will help determine if it is possible to find and enroll patients with chronic refractory cough in a study. It will also look to see if people who have chronic refractory cough also have low levels of zinc in their blood. COCO is a 4-week study with 2 clinic visits. Patients will be asked to fill out a daily Cough Diary while in the study. The ACRC is looking for men or women age 18 or older with chronic cough to enroll in the COCO study. In addition, a small trial, the Pilot of Zinc Acetate to Improve Chronic Cough (ZICO), is being done at 3 ALA ACRC clinical centers: Duke University (North Carolina), National Jewish Health (Colorado), and Mt. Sinai Medical Center (New York). ZICO will look at how well tolerated and how safe taking zinc to treat chronic cough is. Results of COCO and ZICO will be used to develop a full-scale trial to test treating chronic cough with zinc acetate.

If you would like to participate in this trial, please contact the participating center nearest you at the link below.


September 1, 2016 - June 30, 2019


Chronic Cough



Clinical Trials Info
[email protected]

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