Lung Function Outcomes Following Removal of Airway Mucus Plugs in Patients With Asthma (FOCUS)

Not Applicable

Withdrawn

• Conditions: Asthma
• Interventions: Procedure: Therapeutic bronchoscopy for removal of mucus plugs

• Registration Number: NCT05748912
• Lead Sponsor: University of California, San Francisco

Brief Summary

This is a single-center study that will evaluate the safety and tolerability of removal of mucus plugs by bronchoscopy in patients with asthma. This protocol will also plan for the analysis of the features of the mucus plugs removed.

Detailed Description

The investigators' research shows that a large subgroup of asthma patients have mucus plugs, and quantification of these plugs using a bronchopulmonary segment-based scoring system reveals a strong negative correlation between the CT (Computed Tomography) mucus plug score and FEV1 (Forced Expiratory Volume at 1 second). The FOCUS study is a single-center study that has the overarching goal to explore the biology of airway mucus plugs in asthma.

Through the FOCUS study, the investigators will initially explore the safety and tolerability of bronchoscopic removal of airway mucus plugs in patients with asthma and mucus plugs. They will then evaluate potential improvements in lung function outcomes in a dose-dependent manner (i.e., by removing mucus plugs from one lung vs both lungs). A secondary objective of the FOCUS study is to perform detailed cellular and molecular analyses of mucus and epithelial cells from airways impacted with mucus. With these biospecimens, the investigators intend to extend their preliminary findings that mucus plugged airways are characterized by intense type 2 inflammation, determine the mechanisms of epithelial and immune cell reprogramming, as well as how cellular reprogramming affects the promotion and persistence of type 2 airway inflammation.

Study Timeline

• Study Start: 2022-01-26
• Study First Submitted: 2022-01-29
• Study First Submitted QC: 2023-02-17
• Study First Posted: 2023-03-01
• Status Verified: 2025-03
• Primary Completion: 2025-03-25
• Study Completion: 2025-03-25
• Last Update Submitted: 2025-03-26
• Last Update Posted: 2025-04-01

Recruitment & Eligibility

• Status: WITHDRAWN
• Sex: All
• Target Recruitment: 10

Inclusion Criteria

• Males or females between the ages 18 to 70 at the time of visit 1.
• Clinical history of asthma per patient report or medical record.
• Pre-bronchodilator FEV1 < 80% predicted and ≥ 35% predicted
• CT mucus plug score > 5.
• Written informed consent obtained from subject and ability for subject to comply with the requirements of the study.

Exclusion Criteria

• Smoking of tobacco or other recreational inhalants in the last month and/or >10 pack-year smoking history.
• History of other pulmonary disorders including cystic fibrosis and COPD (Chronic Obstructive Pulmonary Disease).
• History of unstable cardiovascular disease.
• BMI > 45
• Current use of anticoagulant medications.
• Upper Respiratory Infection (URI) within the previous 6 weeks
• Currently pregnant and/or unwillingness to practice medically acceptable birth control or complete abstinence during the study
• History of COVID-19 (coronavirus disease) in the past 6 months.

Protocol B:

Inclusion Criteria:

• Males or females between the ages 18 to 80 at the time of visit 1.
• Undergoing clinically indicated bronchoscopy for removal of mucus plugs.
• Clinical history of airway disease (including asthma, COPD and bronchiectasis) per patient report or medical record.
• Written informed consent obtained from subject.

Exclusion Criteria:

• Upper Respiratory Infection (URI) in the past 30 days.
• History of COVID-19 in the past 30 days.
• Currently pregnant during the study.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Therapeutic bronchoscopy for removal of mucus plugs	Therapeutic bronchoscopy for removal of mucus plugs	Protocol A: This protocol will study 10 patients with asthma who have CT (Computed Tomography) evidence of mucus plugs in their airways. Screening data will be reviewed to determine participant eligibility. Participants who meet all eligibility criteria will participate in a bronchoscopy done on one lung for the first 5 participants, and if single lung mucus removal is well tolerated then we will perform bronchoscopies on both lungs for the next 5 participants.

Primary Outcome Measures

Name	Time	Method
Incidence of Treatment-Emergent Adverse Events	Up to 1 week after the research bronchoscopy procedure.	We will monitor the safety and tolerability of mucus plug removal by bronchoscopy by tracking the number of participants with treatment-related adverse events.
Change in FEV1 (Forced Expiratory Volume in the 1st second of Forced Expiration)	1 week after and six months after research bronchoscopy.	We will assess change from baseline FEV1 one week after and six months after removal of mucus plugs by bronchoscopy.

Trial Locations

Locations (1)

UCSF Airway Clinical Research Center; 🇺🇸 San Francisco, California, United States