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Bronchial Thermoplasty in Severe Persistent Asthma

Post-FDA Approval Clinical Trial Evaluating Bronchial Thermoplasty in Severe Persistent Asthma

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01350336
Acronym
PAS2
Enrollment
284
Registered
2011-05-09
Start date
2011-04-07
Completion date
2020-03-17
Last updated
2021-03-05

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Severe Asthma

Brief summary

As Conditions of Approval of the PMA for the Alair System, the FDA requires Boston Scientific to generate data to assess the durability of the BT treatment effect as well as safety data in the intended use population in the United States.

Detailed description

This is a multicenter, open-label, single arm study designed to demonstrate durability of the treatment effect and to evaluate the short-term and longer-term safety profile of the Alair System in the United States in the intended use population (patients 18 years and older with severe persistent asthma).

Interventions

Treatment of airways with the Alair System

Sponsors

Boston Scientific Corporation
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No

Inclusion criteria

1. Subject is an adult between the ages of 18 to 65 years. 2. Subject is able to read, understand, and sign a written Informed Consent to participate in the study and able to comply with the study protocol. 3. Subject has asthma and is taking regular maintenance medication that includes: 1. Inhaled corticosteroid (ICS) at a dosage greater than 1000μg beclomethasone per day or equivalent, AND long acting β2-agonist (LABA) at a dosage of ≥80μg per day Salmeterol or equivalent. 2. Other asthma medications such as leukotriene modifiers, or anti-IgE, are acceptable (Subjects on Xolair® must have been on Xolair for greater than 1 year). 3. Oral corticosteroids (OCS) at a dosage of up to, but not greater than 10mg per day are acceptable.\* 4. Subject has a pre-bronchodilator FEV1 of greater than or equal to 60% of predicted. 5. Subject is a non-smoker for 1 year or greater (if former smoker, less than 10 pack years total smoking history). 6. Subject is able to undergo outpatient (same day) bronchoscopy in the opinion of the investigator or per hospital guidelines. 7. Subject has at least 2 days of asthma symptoms in the last 4 weeks. 8. Subject has an AQLQ score during the baseline period of 6.25 or less. * NOTE: Subjects on a dosage regimen of 20mg OCS every other day may be included as this is equivalent to an average daily dosage of 10mg.

Exclusion criteria

1. Subject is participating in another clinical trial within 6 weeks of the Baseline Period involving respiratory intervention that could affect the outcome measures of this Study. 2. Over the last 7 days of a 4 week medication stable period, subject requirement for rescue medication use other than for prophylactic use for exercise exceeds an average of: 1. 8 puffs per day of short-acting bronchodilator, or 2. 4 puffs per day of long-acting rescue bronchodilator, or 3. 2 nebulizer treatments per day. At the discretion of the Principal Investigator, subjects considered as unstable on baseline medications may have medications adjusted and re-evaluated after a 4 week medication stabilization period. 3. Subject has a post-bronchodilator FEV1 of less than 65%. 4. Subject has a history of life-threatening asthma, defined by past intubation for asthma, or ICU admission for asthma within the prior 2 years. 5. Subject has 3 or more hospitalizations for exacerbations of asthma in the previous year. 6. Subject has had 4 or more infections of lower respiratory tract (LRTI) requiring antibiotics in the past 12 months. 7. Subject has had 4 or more pulses of systemic corticosteroids (tablets, suspension or injection) for asthma symptoms in the past 12 months. 8. Subject has a known sensitivity to medications required to perform bronchoscopy (such as lidocaine, atropine and benzodiazepines). 9. Subject has other respiratory diseases including emphysema, cystic fibrosis, vocal cord dysfunction, mechanical upper airway obstruction, Churg-Strauss syndrome, and allergic bronchopulmonary aspergillosis (asthma, immediate cutaneous reactivity to A. fumigatus, total serum IgE of \>1000ng/mL, elevated specific IgE and IgG to A. fumigatus with or without evidence of central bronchiectasis). 10. Subject has segmental atelectasis, lobar consolidation, significant or unstable pulmonary infiltrate, or pneumothorax, confirmed on x-ray. 11. Subject currently has clinically significant cardiovascular disease, including myocardial infarction, angina, cardiac dysfunction, cardiac dysrhythmia, conduction defect, cardiomyopathy, or stroke. 12. Subject has a known aortic aneurysm. 13. Subject has significant co-morbid illness such as cancer, renal failure, liver disease, or cerebral vascular disease. 14. Subject has uncontrolled hypertension (\>200mm Hg systolic or \>100mm Hg diastolic pressure). 15. Subject has an implanted electrical stimulation device (e.g., a pacemaker, cardiac defibrillator, or deep nerve or deep brain stimulator). 16. Subject has coagulopathy (INR \> 1.5). 17. Subject has any other medical condition that would make them inappropriate for study participation, in the Investigator's opinion.

Design outcomes

Primary

MeasureTime frameDescription
Subjects Experiencing Severe Exacerbations (Rates)Year 1 vs. Year 2, 3, 4, 5The primary endpoint will be the proportion of subjects experiencing severe exacerbations during the subsequent 12-month (for Years 2, 3, 4, and 5) compared to the first 12-month after the Alair treatment.

Secondary

MeasureTime frameDescription
Respiratory Adverse Event RatesYear 1-5A respiratory adverse event is defined as any sign, symptom, illness, clinically significant abnormal laboratory value, or other adverse medical event associated with the Respiratory System that appears or worsens in a subject during a clinical study, regardless of whether or not it is considered related to the procedure used as part of the protocol.
Subjects With Respiratory Adverse EventsYear 1-5A respiratory adverse event is defined as any sign, symptom, illness, clinically significant abnormal laboratory value, or other adverse medical event associated with the Respiratory System that appears or worsens in a subject during a clinical study, regardless of whether or not it is considered related to the procedure used as part of the protocol.
Emergency Room Visits for Respiratory Symptoms RatesYear 1-5Emergency room visits for respiratory symptoms (rates of emergency room visits)
Subjects With Emergency Room Visits for Respiratory SymptomsYear 1-5Subjects with Emergency room visits for respiratory symptoms
Hospitalizations for Respiratory Symptoms RatesYear 1-5(# hospitalizations for respiratory symptoms / subject / year)
Rates of Severe ExacerbationsYear 1-5\# Severe exacerbations / subject / year
Respiratory Serious Adverse Events RatesYear 1-5The rate of subjects with respiratory serious adverse events (SAEs)
Subjects With Respiratory Serious Adverse EventsYear 1-5Subjects with Respiratory Serious Adverse Events
Pre-bronchodilator FEV1Year 1-5% Predicted Pre-bronchodilator FEV1
Post-bronchodilator FEV1Year 1-5% Predicted Post-bronchodilator FEV1
Subjects With Hospitalizations for Respiratory SymptomsYear 1-5Subjects with hospitalizations for respiratory symptoms

Countries

Canada, United States

Participant flow

Participants by arm

ArmCount
Alair
Alair system Alair System: Treatment of airways with the Alair System
279
Total279

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyDeath4
Overall StudyLost to Follow-up31
Overall StudyPhysician Decision8
Overall StudyWithdrawal by Subject14

Baseline characteristics

CharacteristicAlair
Age, Continuous45.71 years
AQLQ4.03 AQLQ Score
STANDARD_DEVIATION 1.28
BMI32.2 kg/m2
FEV1 - % Predicted
Post-bronchodilator FEV1
85.8 % Predicted
STANDARD_DEVIATION 13.6
FEV1 - % Predicted
Pre-bronchodilator FEV1
80.4 % Predicted
STANDARD_DEVIATION 13.7
Height167.4 cm
Prior 12 months - Event rates
ER visits for asthma
0.54 # events / subject
STANDARD_DEVIATION 1.2
Prior 12 months - Event rates
Hospitalizations for asthma
0.22 # events / subject
STANDARD_DEVIATION 0.53
Prior 12 months - Event rates
Severe Exacerbations
1.61 # events / subject
STANDARD_DEVIATION 1.12
Prior 12 months - % Subjects
ER visits for asthma
82 Participants
Prior 12 months - % Subjects
Hospitalization for asthma
45 Participants
Prior 12 months - % Subjects
Severe Exacerbations
217 Participants
Race/Ethnicity, Customized
American Indian or Alaska native
3 Participants
Race/Ethnicity, Customized
Asian
4 Participants
Race/Ethnicity, Customized
Black, of African Heritage
25 Participants
Race/Ethnicity, Customized
Caucasian
234 Participants
Race/Ethnicity, Customized
Hispanic or Latino
8 Participants
Race/Ethnicity, Customized
Other
5 Participants
Sex: Female, Male
Female
180 Participants
Sex: Female, Male
Male
99 Participants
Weight90.3 kg

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
4 / 279
other
Total, other adverse events
268 / 279
serious
Total, serious adverse events
130 / 279

Outcome results

Primary

Subjects Experiencing Severe Exacerbations (Rates)

The primary endpoint will be the proportion of subjects experiencing severe exacerbations during the subsequent 12-month (for Years 2, 3, 4, and 5) compared to the first 12-month after the Alair treatment.

Time frame: Year 1 vs. Year 2, 3, 4, 5

Population: Primary Endpoint - the proportion of subjects experiencing severe exacerbations during the subsequent 12-month (for Years 2, 3, 4, and 5) compared to the first 12-month after the Alair treatment.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Year 1Subjects Experiencing Severe Exacerbations (Rates)132 Participants
Year 2Subjects Experiencing Severe Exacerbations (Rates)118 Participants
Year 3Subjects Experiencing Severe Exacerbations (Rates)118 Participants
Year 4Subjects Experiencing Severe Exacerbations (Rates)106 Participants
Year 5Subjects Experiencing Severe Exacerbations (Rates)97 Participants
Comparison: Comparison of Years 1 and 295% CI: [-0.1251, 0.0497]
Comparison: Comparison of Years 1 and 395% CI: [-0.1197, 0.0565]
Comparison: Comparison of Years 1 and 495% CI: [-0.1444, 0.0329]
Comparison: Comparison of Years 1 and 595% CI: [-0.1661, 0.013]
Secondary

Emergency Room Visits for Respiratory Symptoms Rates

Emergency room visits for respiratory symptoms (rates of emergency room visits)

Time frame: Year 1-5

ArmMeasureValue (MEAN)Dispersion
Year 1Emergency Room Visits for Respiratory Symptoms Rates.31 # ER Visit / subject / yearStandard Deviation 0.87
Year 2Emergency Room Visits for Respiratory Symptoms Rates.24 # ER Visit / subject / yearStandard Deviation 0.8
Year 3Emergency Room Visits for Respiratory Symptoms Rates.21 # ER Visit / subject / yearStandard Deviation 0.65
Year 4Emergency Room Visits for Respiratory Symptoms Rates.17 # ER Visit / subject / yearStandard Deviation 0.56
Year 5Emergency Room Visits for Respiratory Symptoms Rates.13 # ER Visit / subject / yearStandard Deviation 0.49
Secondary

Hospitalizations for Respiratory Symptoms Rates

(# hospitalizations for respiratory symptoms / subject / year)

Time frame: Year 1-5

ArmMeasureValue (MEAN)Dispersion
Year 1Hospitalizations for Respiratory Symptoms Rates0.13 # Hospitalizations / subject / yearStandard Deviation 0.5
Year 2Hospitalizations for Respiratory Symptoms Rates0.11 # Hospitalizations / subject / yearStandard Deviation 0.47
Year 3Hospitalizations for Respiratory Symptoms Rates0.11 # Hospitalizations / subject / yearStandard Deviation 0.47
Year 4Hospitalizations for Respiratory Symptoms Rates0.05 # Hospitalizations / subject / yearStandard Deviation 0.28
Year 5Hospitalizations for Respiratory Symptoms Rates0.06 # Hospitalizations / subject / yearStandard Deviation 0.31
Secondary

Post-bronchodilator FEV1

% Predicted Post-bronchodilator FEV1

Time frame: Year 1-5

ArmMeasureValue (MEAN)Dispersion
Year 1Post-bronchodilator FEV193.1 % PredictedStandard Deviation 13.9
Year 2Post-bronchodilator FEV192.3 % PredictedStandard Deviation 14.1
Year 3Post-bronchodilator FEV191.8 % PredictedStandard Deviation 14.2
Year 4Post-bronchodilator FEV191.1 % PredictedStandard Deviation 14.4
Year 5Post-bronchodilator FEV191.0 % PredictedStandard Deviation 14.3
Secondary

Pre-bronchodilator FEV1

% Predicted Pre-bronchodilator FEV1

Time frame: Year 1-5

ArmMeasureValue (MEAN)Dispersion
Year 1Pre-bronchodilator FEV189.6 % PredictedStandard Deviation 14.5
Year 2Pre-bronchodilator FEV189.3 % PredictedStandard Deviation 14.6
Year 3Pre-bronchodilator FEV187.7 % PredictedStandard Deviation 14.9
Year 4Pre-bronchodilator FEV188.5 % PredictedStandard Deviation 13.8
Year 5Pre-bronchodilator FEV187.4 % PredictedStandard Deviation 14.6
Secondary

Rates of Severe Exacerbations

\# Severe exacerbations / subject / year

Time frame: Year 1-5

ArmMeasureValue (MEAN)Dispersion
Year 1Rates of Severe Exacerbations0.93 # Severe Exacerbations / subject / yearStandard Deviation 1.35
Year 2Rates of Severe Exacerbations.92 # Severe Exacerbations / subject / yearStandard Deviation 1.21
Year 3Rates of Severe Exacerbations.77 # Severe Exacerbations / subject / yearStandard Deviation 1.01
Year 4Rates of Severe Exacerbations.84 # Severe Exacerbations / subject / yearStandard Deviation 1.23
Year 5Rates of Severe Exacerbations.72 # Severe Exacerbations / subject / yearStandard Deviation 1.13
Secondary

Respiratory Adverse Event Rates

A respiratory adverse event is defined as any sign, symptom, illness, clinically significant abnormal laboratory value, or other adverse medical event associated with the Respiratory System that appears or worsens in a subject during a clinical study, regardless of whether or not it is considered related to the procedure used as part of the protocol.

Time frame: Year 1-5

ArmMeasureValue (MEAN)Dispersion
Year 1Respiratory Adverse Event Rates1.70 # Resp. AE / subject / yearStandard Deviation 1.95
Year 2Respiratory Adverse Event Rates1.52 # Resp. AE / subject / yearStandard Deviation 1.66
Year 3Respiratory Adverse Event Rates1.28 # Resp. AE / subject / yearStandard Deviation 1.42
Year 4Respiratory Adverse Event Rates1.35 # Resp. AE / subject / yearStandard Deviation 1.63
Year 5Respiratory Adverse Event Rates1.22 # Resp. AE / subject / yearStandard Deviation 1.92
Secondary

Respiratory Serious Adverse Events Rates

The rate of subjects with respiratory serious adverse events (SAEs)

Time frame: Year 1-5

ArmMeasureValue (MEAN)Dispersion
Year 1Respiratory Serious Adverse Events Rates0.14 # Respiratory SAEs / subect / yearStandard Deviation 0.5
Year 2Respiratory Serious Adverse Events Rates0.11 # Respiratory SAEs / subect / yearStandard Deviation 0.37
Year 3Respiratory Serious Adverse Events Rates0.10 # Respiratory SAEs / subect / yearStandard Deviation 0.41
Year 4Respiratory Serious Adverse Events Rates0.06 # Respiratory SAEs / subect / yearStandard Deviation 0.33
Year 5Respiratory Serious Adverse Events Rates0.06 # Respiratory SAEs / subect / yearStandard Deviation 0.28
Secondary

Subjects With Emergency Room Visits for Respiratory Symptoms

Subjects with Emergency room visits for respiratory symptoms

Time frame: Year 1-5

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Year 1Subjects With Emergency Room Visits for Respiratory Symptoms48 Participants
Year 2Subjects With Emergency Room Visits for Respiratory Symptoms37 Participants
Year 3Subjects With Emergency Room Visits for Respiratory Symptoms32 Participants
Year 4Subjects With Emergency Room Visits for Respiratory Symptoms28 Participants
Year 5Subjects With Emergency Room Visits for Respiratory Symptoms18 Participants
Secondary

Subjects With Hospitalizations for Respiratory Symptoms

Subjects with hospitalizations for respiratory symptoms

Time frame: Year 1-5

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Year 1Subjects With Hospitalizations for Respiratory Symptoms21 Participants
Year 2Subjects With Hospitalizations for Respiratory Symptoms19 Participants
Year 3Subjects With Hospitalizations for Respiratory Symptoms18 Participants
Year 4Subjects With Hospitalizations for Respiratory Symptoms8 Participants
Year 5Subjects With Hospitalizations for Respiratory Symptoms11 Participants
Secondary

Subjects With Respiratory Adverse Events

A respiratory adverse event is defined as any sign, symptom, illness, clinically significant abnormal laboratory value, or other adverse medical event associated with the Respiratory System that appears or worsens in a subject during a clinical study, regardless of whether or not it is considered related to the procedure used as part of the protocol.

Time frame: Year 1-5

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Year 1Subjects With Respiratory Adverse Events184 Participants
Year 2Subjects With Respiratory Adverse Events165 Participants
Year 3Subjects With Respiratory Adverse Events155 Participants
Year 4Subjects With Respiratory Adverse Events141 Participants
Year 5Subjects With Respiratory Adverse Events133 Participants
Secondary

Subjects With Respiratory Serious Adverse Events

Subjects with Respiratory Serious Adverse Events

Time frame: Year 1-5

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Year 1Subjects With Respiratory Serious Adverse Events26 Participants
Year 2Subjects With Respiratory Serious Adverse Events25 Participants
Year 3Subjects With Respiratory Serious Adverse Events17 Participants
Year 4Subjects With Respiratory Serious Adverse Events10 Participants
Year 5Subjects With Respiratory Serious Adverse Events11 Participants

Source: ClinicalTrials.gov · Data processed: Feb 20, 2026