Interferon-alpha Treatment of Chronic Cough in Chronic Obstructive Pulmonary Disease and Idiopathic Pulmonary Fibrosis

Both chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF)
frequently lead to a chronic cough that negatively impacts the quality of life (QOL) for
patients and those around them. This is a randomized, double-blind, placebo-controlled trial
to determine whether interferon-alpha, delivered in low doses via orally dissolving lozenges
given 3 times per day for 4 weeks, can reduce the frequency and severity of chronic cough in
patients with COPD or IPF. Cough frequency will be assessed via 24-hour digital audio
recordings made prior to entry, and at weeks 2 and 4 of treatment. Cough severity will be
assessed via a 100-mm visual analog scale questionnaire completed by the subject prior to
entry and then weekly during treatment. Subjects will also complete questionnaires regarding
cough frequency, duration and intensity, QOL, dyspnea, and antitussive medication usage
weekly during treatment. All questionnaires will be repeated weekly during a 4-week
post-treatment observation period to assess durability of response.

Inclusion Criteria:

For all patients

- history of clinically significant chronic cough for > 3 months

- For COPD patients

- >40 years of age

- 20-pack-year history of smoking

- GOLD classification of Stage 1 or higher

- For IPF patients

- > 50 years of age

- history of unexplained dyspnea on exertion of > 3 months

- exhibits coughing and bilateral, basilar, inspiratory crackles on physical exam

- presents as being in a stable phase of IPF

- lung biopsy or HRCT indicative of IPF

Exclusion Criteria:

- ACE inhibitor use

- GERD

- current cancer or history of lung cancer

- non-ambulatory

- hospitalized in the previous 12 months for heart failure