Elucidation of Acid-Induced Pulmonary Inflammation

Asthma Clinical Trial

Official title: Elucidation of Acid-Induced Pulmonary Inflammation

Status Completed

Clinical Trial Summary

We propose to study how heartburn may lead to different types of inflammation in one's airways. Additionally, we hope to determine whether aggressive treatment of heartburn results in improvement in both symptoms of heartburn and asthma but also in documented improvement in airway inflammation as determined by biopsy. The results of this study will be important in directing future research into the relationship between heartburn and asthma and may provide a clue whether certain subtypes of asthma may be caused primarily by GER.

Clinical Trial Description

Currently, many Americans suffer from asthma. The exact mechanism by which airway inflammation leads to asthma symptoms has yet to be clearly explained. In previous studies, persons with asthma appear to have different types of inflammation in their lungs. The reasons for this difference remain a mystery. Allergy is known to play a role in bronchospasm. Other mechanisms have not been discovered.

It is known that asthma and heartburn are correlated. Studies have confirmed a direct relationship between cough and heartburn (Gastroesophageal reflux). Other researchers have determined that asthma is often worsened by gastroesophageal reflux (GER). Determination of the exact relationship between these two entities remains unclear.

We propose that heartburn may contribute to airway inflammation in asthmatics, resulting in different patterns of inflammation between those people with and without GER. In fact, adult-onset asthma may result primarily from longstanding heartburn. This has yet to be proven.

We propose to study how heartburn may lead to different types of inflammation in one's airways. Additionally, we hope to determine whether aggressive treatment of heartburn results in improvement in both symptoms of heartburn and asthma but also in documented improvement in airway inflammation as determined by biopsy. The results of this study will be important in directing future research into the relationship between heartburn and asthma and may provide a clue whether certain subtypes of asthma may be caused primarily by GER.

A total of 30 subjects will be studied, randomized to twice daily esomeprazole versus placebo. Study procedures are as follows:

A. Esophageal studies and validated questionnaires:

Patients will be evaluated with validated SF-36 Quality of Life Questionnaire, Mini-asthma Quality of Life Questionnaire, and GER Questionnaire 35-7. Patients will undergo esophageal manometry and pH detection with a 24- hour pH probe to confirm the presence of pathologic GER.

B. Bronchoscopy:

After an overnight fast, subjects will report to the bronchoscopy suite as directed. Bronchoscopy with bronchoalveolar lavage and bronchial biopsy will be performed by Dr. Wayne Samuelson following the University of Utah's standardized protocol. Bronchoscopy and endobronchial biopsies present minimal risk to asthmatic airways when performed by appropriate, trained personnel.40-42 Conscious sedation with intravenous remifentanyl and propofol will be administered by a trained nurse experienced in conscious sedation. The nose and pharynx will be anesthetized with 1% lidocaine administered by nebulization and by lidocaine jelly administered topically to the nasal mucosa. Additional lidocaine will be administered via the bronchoscope to the vocal cords, trachea, main carina and mainstem bronchi. The total dose of lidocaine will not exceed 400 mg 43. All subjects will have continuous cardiac and oxygen saturation monitoring and will receive supplemental oxygen during the procedure sufficient to maintain SpO2 > 90%.

The subject will be placed in a recumbent position and the bronchoscope will be introduced via the nose. After passing the vocal cords, the bronchoscope will be introduced via the right mainstem bronchus into the right middle lobe where it will be wedged into a segmental bronchus. (Should, for any reason, the right middle lobe be inaccessible, the same procedure will be used to wedge the bronchoscope into a lingular segment in the left lung.) A 60 cc aliquot of room temperature normal saline will be instilled through the bronchoscope and recovered using the same syringe. This procedure will be repeated three more times (total lavage volume of 240 cc) and the recovered volumes will be pooled and measured. Forceps biopsies of respiratory mucosa will then be taken from the trachea, main carina, bronchus intermedius and right middle lobe areas. Two to six biopsies will be taken from each site. Specific tissue from each site will be frozen and stored for future use.

Individuals will be randomized to esomeprazole 40 mg twice daily or placebo (all patients will undergo lifestyle modification for reflux). It has been determined in previous studies that higher levels of acid suppression are needed to result in clinical improvement in asthma.52 The drug will be taken for 3-5 months. The variable duration of drug consumption allows for stabilization of medical therapy prior to repeat biopsies (if needed).

Patients will be monitored by telephone at monthly intervals. Rescue inhaler use, hospitalizations, exercise tolerance, and study compliance will be assessed and recorded to document clinical progress. Patients will be asked to maintain their standard inhaler therapy (especially that of inhaled steroids). Any changes to the therapy will be immediately reported to the investigators. If subjects experience an acute flare, appropriate medications will be given until the patient is stable to return to their initial inhaler regimen. The variable time frame for repeat bronchoscopy (3-5 months) was chosen to allow for stabilization of inhaler regimen (if this was disrupted) prior to repeat biopsies. If patients remain on stable medication throughout the trial, repeat bronchoscopy will be performed at 3 months.

After 2 months of therapy, the mini-asthma quality of life instrument and SF-36 will be administered again. This will also administered at the end of the trial.

After 3-5 months, patients will once again undergo bronchoscopy with BAL/biopsies. Cytokine protein arrays will be repeated. Comparisons will then be made intra-group before and after therapy. Additional comparisons of inflammation and bronchial hyper-responsiveness will be made between groups. Randomization will allow the investigators to control for any changes in cytokine patterns due to seasonal affect (if both groups reduce the concentration of IL-5 in a similar pattern, this is more likely seasonal than due to acid suppression). ;

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Alveolitis, Extrinsic Allergic
• Asthma
• Gastroesophageal Reflux
• Pneumonia

• NCT number: NCT00361972
• Study type: Interventional
• Source: University of Utah
• Status: Completed
• Phase: Phase 2/Phase 3
• Start date: August 2006
• Completion date: April 2009