image: Severe asthma attacks reduced by bronchial thermoplasty. view more
Credit: ATS
ATS 2017, WASHINGTON, DC -- In a new study presented at the 2017 American Thoracic Society International Conference, adult asthma patients treated with bronchial thermoplasty (BT) had fewer severe exacerbations and were able to reduce their ER visits and hospitalizations in the two years following treatment. Approved by the FDA in 2010, BT is a new device-based therapy that uses a series of three radio-frequency treatments to open the airways of adults with severe, persistent asthma whose symptoms are not adequately controlled by inhaled corticosteroids or long-acting beta-agonists.
To date, more than 6,800 patients in 33 countries have been treated with BT.
The "Post-FDA Approval Clinical Trial Evaluating BT in Severe Persistent Asthma" (PAS2 study), which involves hundreds of patients at dozens of research centers, looks at the long-term effects and safety of BT.
"The results of the PAS2 study suggest that after a single series of BT procedures, patients experience long-term improvement in their asthma control," said lead author Geoffrey Chupp, MD, from Yale School of Medicine. "These results indicate that BT works across the spectrum of severe asthma patients. We believe BT should be more widely considered as a treatment option in patients with poorly controlled severe asthma."
Two-hundred eighty four patients were enrolled in the study at 27 centers in the U.S. and Canada. Two-hundred seventy-nine study subjects had at least one BT procedure, and 271 had all three procedures. In the 12 months prior to the first BT procedure, 78 percent of subjects had at least one severe exacerbation, 16 percent required hospitalization and 29 percent had ER visits. In the first year follow up, 50.6 percent had severe exacerbations; 45.4 percent had exacerbations in the second year follow up. Asthma-related hospitalizations and ER visits also saw significant, continuing reductions: 14.4 percent and 12.7 percent of subjects had hospitalizations, respectively, in the first and second year, and 18.3 percent and 13.5 percent made ER visits in the first and second year post-treatment.
"On average, patients also reduced their inhaled corticosteroid dose and a significant number were able to discontinue maintenance oral corticosteroids," said Dr. Chupp. "BT offers an alternative approach for patients who are inadequately controlled with medications designed to improve the control of their asthma."
###
Contact for Media: Geoffrey Chupp, MD, Geoffrey.chupp@yale.edu
Abstract 5767
Post-Approval Study for Bronchial Thermoplasty (BT): Results to 2 Years
Authors: G. Chupp1, J. Kline2, S.B. Khatri3, C. McEvoy4, G.A. Silvestri5, A. Shifren6, S. Bansal7, M. McClelland8, M. Dransfield9, R. Olivenstein10, E. Lawson11, M. Simoff12, M.M. Wahidi13, C.R. Lamb14, S. Ferguson15, A. Haas16, K. Hogarth17, R. Tejedor18, J. Toth19, A. Majid20, S. Rafeq21, J.M. Fitzgerald22, K. Enfield23, G.M. Grubb24, E. McMullen24, M. Laviolette25; 1Yale University - New Haven, CT/US, 2University of Iowa Hospitals and Clinics - Iowa City, IA/US, 3Cleveland Clinic Respiratory Institute - Cleveland, OH/US, 4Regions Hospital - St. Paul, MN/US, 5Medical University of South Carolina - Charleston, SC/US, 6Washington University School of Medicine - St. Louis, MO/US, 7Dubois Regional Medical Center - DuBois, PA/US, 8Spectrum Health Hospitals - Grand Rapids, MI/US, 9University of Alabama - Birmingham, AL/US, 10Montreal Chest Institute, McGill University - Montreal, QC/CA, 11Surrey Memorial Hospital - Surrey, BC/CA, 12Henry Ford Hospital - Detroit, MI/US, 13Duke University Medical Center - Durham, NC/US, 14Lahey Hospital and Medical Center - Burlington, MA/US, 15University of Wisconsin Madison - Madison, WI/US, 16University of Pennsylvania - Philadelphia, PA/US, 17University of Chicago - Chicago, IL/US, 18LSU Health Science Center - New Orleans, LA/US, 19Penn State University - Hershey, PA/US, 20Beth Israel Deaconess Medical Center - Boston, MA/US, 21St. Elizabeth's Medical Center, Tufts Medical School - Boston, MA/US, 22University of British Columbia - Vancouver, BC/CA, 23University of Virginia Health System - Charlottesville, VA/US, 24Boston Scientific - Marlborough, MA/US, 25Laval University - Québec, QC/CA
Rationale: Bronchial thermoplasty (BT) is a non-pharmacologic, device-based treatment for subjects ?18 years with severe persistent asthma not well controlled with inhaled corticosteroids (ICS) and long-acting beta-agonists (LABA). The "Post-FDA Approval Clinical Trial Evaluating BT in Severe Persistent Asthma" (PAS2 study) collects real-world data on subjects undergoing BT treatment with the Alair BT System. We report for the first time baseline and follow-up results for the primary and secondary endpoints to 2 years.
Methods: The PAS2 study is a prospective, open-label, observational, multi-center trial at US and Canadian centers. Subjects 18-65 years taking ICS ?1000μg/day (beclomethasone or equivalent) and LABA ?80μg/day (salmeterol or equivalent) were enrolled. Additional inclusion criteria were: pre-bronchodilator FEV1 ?60% predicted, non-smoker for ?1 year (<10 pack/years if former smoker), ?2 days with asthma symptoms in the last 4 weeks, AQLQ ?6.25, and in the 12 months prior to BT treatment have ?2 hospitalizations, ?3 lower respiratory tract infections, and ?3 severe exacerbations. Subjects diagnosed with other severe respiratory diseases were excluded. Baseline demographics, AQLQ, medication usage, FEV1 and FVC, medical history, comorbidities, and 12-month baseline recall data (severe exacerbations and healthcare utilization) were recorded. Following BT, severe exacerbations, hospitalization, and ER visits, as well as FEV1 and FVC, were evaluated for each subject at 1 and 2 years post-therapy.
Results: Two-hundred eighty-four subjects were enrolled at 27 centers; 279 subjects had at least 1 of 3 BT procedures; 271 subjects had all 3 BT procedures. Subjects had mean age 45.7 years with 64.5% female and mean BMI 32.2kg/m2. Mean ICS dose was 2269μg/day, LABA dose was 74μg/day, and SABA dose was 2.35μg/day at baseline. Baseline mean AQLQ was 4.03 with a mean of 25.2 years since asthma diagnosis. In the 12 months prior to first BT procedure, 78% of subjects had at least one severe exacerbation (mean 1.6/subject), 16% had hospitalizations, and 29% had ER visits. In the first and second year of follow-up, 50.6% and 45.4% of subjects had severe exacerbations, respectively. Similarly, 14.4% and 12.7% of subjects had hospitalizations in the first and second year of follow-up, and 18.3% and 13.5% of subjects had ER visits in the first and second year of follow-up.
Conclusion: The PAS2 study shows that compared to the year prior to BT treatment, in the 2 years after BT treatment study subjects experienced improved asthma control with respect to severe exacerbations, hospitalizations and ER visits.
Funding: Boston Scientific
PAS2 Study - Baseline and 1- and 2-Year Results
Variable
Baseline
1-Year
Follow-up
2-Year
Follow-up
Demographics
Age (yr)
45.71±11.62
(279)
(18.00, 66.00)
--
--
Female
64.5% (180/279)
--
--
Body Mass Index (BMI) [kg/m2]
32.20±7.46
(279)
(18.18, 61.27)
--
--
Baseline Medication usage
ICS Dose (μg/day)
2268.77±780.10
(278)
(750.00,
6480.00)
--
--
LABA Dose (μg/day)
73.77±40.82
(278)
(18.00, 218.00)
--
--
Short-Acting Beta Agonists (SABA) used per day for asthma symptoms (μg/day)
2.35±1.51 (263)
(0.00, 18.00)
--
--
Quality of Life Measurement
AQLQ
4.03±1.28 (279)
(1.50, 6.59)
--
--
Medical History
How long has the subject been diagnosed with asthma (years)
25.23±14.90
(279)
(1.00, 60.00)
--
--
Spirometry
FEV1
Pre-bronchodialator
Measured value (liters)
2.57±0.65 (279)
(1.19, 4.93)
2.47±0.75
(258)
(0.79, 5.06)
2.49±0.77
(218)
(0.97, 4.94)
% predicted
80.40±13.73
(279)
(59.52, 125.93)
78.16±18.67
(258)
(33.15,
132.11)
78.86±17.65
(218)
(30.71,
130.43)
Post-bronchodialator
Measured value (liters)
2.74±0.66 (279)
(1.28, 5.18)
2.64±0.73
(257)
(0.81, 5.25)
2.64±0.76
(217)
(1.03, 5.13)
% predicted
85.78±13.64
(279)
(64.71, 130.69)
83.65±17.12
(257)
(34.50,
137.08)
83.90±16.45
(217)
(29.89,
135.00)
FVC
Pre-bronchodialator
Measured value (liters)
3.66±0.90 (279)
(1.44, 6.79)
3.58±0.95
(258)
(1.55, 6.21)
3.58±0.99
(218)
(1.38, 6.20)
% predicted
91.09±13.13
(279)
(57.78, 134.17)
89.57±14.46
(258)
(56.05,
134.20)
89.72±14.28
(218)
(54.83,
133.48)
Variable
Baseline
1-Year
Follow-up
2-Year
Follow-up
Post-bronchodilator
Measured value (liters)
3.79±0.92 (279)
(1.57, 6.59)
3.72±0.96
(257)
(1.49, 6.19)
3.69±0.99
(217)
(1.42, 6.53)
% predicted
94.59±12.92
(279)
(59.78, 129.91)
93.05±13.92
(257)
(53.74,
137.64)
92.64±13.56
(217)
(59.17,
134.02)
Healthcare Utilization and Severe Exacerbations
Severe exacerbations
% subjects with severe exacerbations
77.8% (217/279)
50.6% (133/263)
45.4% (104/229)
# severe exacerbations
1.61±1.12 (279)
(0.00, 3.00)
0.92±1.33
(263)
(0.00, 12.00)
0.87±1.17
(229)
(0.00, 5.00)
Hospitalizations for asthma
% subjects with hospitalizations
16.1% (45/279)
14.4% (38/263)
12.7% (29/229)
# hospitalizations
0.22±0.53 (279)
(0.00, 2.00)
0.13±0.50
(263)
(0.00, 3.00)
0.10±0.45
(229)
(0.00, 5.00)
ER visits for asthma
% subjects with ER visits
29.4% (82/279)
18.3% (48/263)
13.5% (31/229)
# ER visits
0.54±1.20 (279)
(0.00, 10.00)
0.30±0.87
(263)
(0.00, 9.00)
0.24±0.87
(229)
(0.00, 9.00
FOR MORE INFORMATION, CONTACT:
Dacia Morris
dmorris@thoracic.org
ATS Office 212-315-8620 (until May 17)
Cell Phone 917-561-6545
Session: A7043 Novel Therapeutic Targets in Obstructive Lung Disease
Abstract Presentation Time: Wednesday, May 24, 2017, 9:15-9:30 a.m. ET
Location: Marquis Ballroom 6 (Level M2), Marriott Marquis Washington