The goal of this clinical trial is to evaluate whether inhaled Treprostinil (Tyvaso) can improve oxygen delivery and blood flow in the lungs in adults (age ≥40) with chronic obstructive pulmonary disease (COPD) and hypoxemia who have less severe reduction in lung blood volume (diffusing capacity of the lungs for carbon monoxide \[DLCO\] ≥45%). The main questions it aims to answer are: 1. Does inhaled Treprostinil increase pulmonary capillary blood volume in ventilated lung regions, as measured by hyperpolarized xenon-129 magnetic resonance imaging (HP129Xe MRI)? 2. Does inhaled Treprostinil improve oxygen delivery (measured as red blood cell \[RBC\] chemical shift) and maintain or only slightly change pulmonary vascular resistance (measured by RBC oscillation amplitude)? 3. Can pre-treatment MRI parameters (RBC transfer and RBC oscillation amplitude) predict who will respond to inhaled Treprostinil? Participants will: * Use the Tyvaso nebulizer (inhaled Treprostinil) 4 times daily for 4 weeks, starting at 3 breaths per session and increasing to a maximum of 6 breaths per session as tolerated. * Undergo HP129Xe MRI before and after treatment to assess regional lung function and oxygen exchange. * Complete pulmonary function tests (PFTs), 6-minute walk tests (6MWT), and echocardiograms at the beginning and end of the study. * Be monitored for adverse events, with a phone check-in midway through and after the treatment period.
This is a single-arm, proof-of-concept study evaluating the effects of inhaled Treprostinil (Tyvaso nebulizer) on regional gas exchange and capillary blood oxygenation in patients with chronic obstructive pulmonary disease (COPD) and hypoxemia. The study will enroll 10 outpatient subjects aged ≥40 with a chronic bronchitis phenotype, confirmed COPD diagnosis, and a diffusing capacity of the lungs for carbon monoxide (DLCO) ≥45% predicted. All participants will receive inhaled Treprostinil via a 4-week dose titration protocol (starting at 3 breaths four times daily and increasing to 6 breaths as tolerated). The primary objectives are to "determine the effects of inhaled Treprostinil on regional gas exchange and capillary blood oxygenation as measured by hyperpolarized xenon-129 magnetic resonance imaging (HP129Xe MRI), including ventilation defect percentage (VDP), membrane defect percentage, red blood cell (RBC) transfer defect percentage and normalized RBC oscillation amplitude and RBC frequency shift," and to "determine whether pre-treatment VDP, membrane defect percentage, RBC transfer defect percentage, RBC chemical shift and normalized RBC oscillation amplitude predict a positive response to inhaled Treprostinil." Assessments will include HP129Xe MRI, spirometry with DLCO, 6-minute walk testing (6MWT), and echocardiography at baseline and after 4 weeks. Data will be analyzed for changes in regional lung function and oxygenation. Safety monitoring will focus on known adverse effects of inhaled Treprostinil including "cough, headache, hypotension, oropharyngeal pain, throat irritation and nausea," and will address more serious risks observed in the PERFECT trial (COPD exacerbation, respiratory failure, myocardial infarction, and death). By selecting subjects with DLCO ≥45% predicted and using a shorter 4-week treatment duration with titrated dosing, the study aims to mitigate these risks.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
TREATMENT
Masking
NONE
Enrollment
10
Participants will receive inhaled Treprostinil (Tyvaso nebulizer), 6 µg per breath, administered four times daily for 4 weeks. The starting dose will be 3 breaths per session. The dose will increase by 1 breath per session each week, as tolerated, to a target of 6 breaths per session by week 4. If adverse effects occur, participants will remain at the highest tolerated dose. The drug will be administered using the Tyvaso inhalation system provided by United Therapeutics. No changes to baseline COPD maintenance medications are allowed during the treatment period. Participants will be monitored for safety throughout the study.
Duke Asthma Allergy and Airway Center
Durham, North Carolina, United States
RECRUITINGVentilation Defect Percentage (VDP) on HP129XeMRI
Defined as the region with ventilation signals \< mean - 2SD, measured by HP129XeMRI and expressed as a percentage of total lung volume.
Time frame: Baseline and 4 weeks post-Tyvaso
Membrane Defect Percentage on HP129XeMRI
Defined as the region with membrane signals \< mean - 2SD, measured by HP129XeMRI and expressed as a percentage of total lung volume.
Time frame: Baseline and 4 weeks post-Tyvaso
Low Membrane Region Percentage on HP129XeMRI
Defined as the region with membrane signals between 1SD and 2SD below the mean, measured by HP129XeMRI and expressed as a percentage of total lung volume.
Time frame: Baseline and 4 weeks post-Tyvaso
RBC Transfer Defect Percentage on HP129XeMRI
Defined as the region with RBC transfer signals \< mean - 2SD, measured by HP129XeMRI and expressed as a percentage of total lung volume.
Time frame: Baseline and 4 weeks post-Tyvaso
Low RBC Transfer Region Percentage on HP129XeMRI
Defined as the region with RBC transfer signals between 1SD and 2SD below the mean, measured by HP129XeMRI and expressed as a percentage of total lung volume.
Time frame: Baseline and 4 weeks post-Tyvaso
RBC Oscillation Amplitude Normalized for RBC Transfer Defect
Measured using HP129XeMRI spectroscopy as a surrogate for pulmonary vascular resistance, normalized to RBC transfer signal intensity.
Time frame: Baseline and 4 weeks post-Tyvaso
RBC Chemical Shift on HP129XeMRI Spectroscopy
Frequency shift in RBC signal reflecting capillary blood oxygenation, measured using HP129XeMRI spectroscopy.
Time frame: Baseline and 4 weeks post-Tyvaso
Nadir SpO₂ During 6MWT
Lowest oxygen saturation (SpO₂) recorded during the 6-minute walk test, measured by pulse oximetry. The test is performed on room air unless SpO₂ drops below 89%, at which point supplemental oxygen is administered to maintain SpO₂ ≥89%.
Time frame: Baseline and 4 weeks post-Tyvaso treatment
Supplemental Oxygen Flow During 6MWT
Oxygen flow rate in liters per minute required to maintain SpO₂ ≥89% during the 6-minute walk test if room air is insufficient.
Time frame: Baseline and 4 weeks post-Tyvaso treatment
6-Minute Walk Distance (6MWD)
Total distance walked in meters during the 6-minute walk test, following ATS guidelines.
Time frame: Baseline and 4 weeks post-Tyvaso treatment
Dyspnea Score During 6MWT
Subjective rating of dyspnea severity on a 1-10 scale reported by participants at the end of the 6-minute walk test.
Time frame: Baseline and 4 weeks post-Tyvaso treatment
Peak Heart Rate (% Predicted) During 6MWT
Highest heart rate achieved during the 6-minute walk test, expressed as a percentage of predicted maximum heart rate.
Time frame: Baseline and 4 weeks post-Tyvaso treatment
Forced Expiratory Volume in 1 Second (FEV1) - Absolute and % Predicted
EV1 measured in liters and as a percentage of predicted value, assessed by spirometry.
Time frame: Baseline and 4 weeks post-Tyvaso treatment
Forced Vital Capacity (FVC) - Absolute and % Predicted
FVC measured in liters and as a percentage of predicted value, assessed by spirometry
Time frame: Baseline and 4 weeks post-Tyvaso treatment
Total Lung Capacity (TLC) - Absolute and % Predicted
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TLC measured in liters and as a percentage of predicted value, assessed by lung volume testing.
Time frame: Baseline and 4 weeks post-Tyvaso treatment
Residual Volume (RV) - Absolute and % Predicted
RV measured in liters and as a percentage of predicted value, assessed by lung volume testing.
Time frame: Baseline and 4 weeks post-Tyvaso treatment
Diffusing Capacity for Carbon Monoxide (DLCO) - Absolute and % Predicted
DLCO measured in mL/min/mmHg and as a percentage of predicted value, assessed by single-breath method.
Time frame: Baseline and 4 weeks post-Tyvaso treatment
Carbon Monoxide Transfer Coefficient (KCO) - Absolute and % Predicted
KCO measured in mL CO/min/mmHg/L and as a percentage of predicted value, derived from DLCO and alveolar volume.
Time frame: Baseline and 4 weeks post-Tyvaso treatment