The Impact of Inhaled Treprostinil Sodium Inhalation on Ventilation Perfusion Matching Used in Patients With Group 1 PAH With Concomitant COPD

Abstract

SESSION TITLE: Pulmonary Arterial Hypertension Posters II SESSION TYPE: Original Investigation Poster PRESENTED ON: Wednesday, October 28, 2015 at 01:30 PM - 02:30 PM PURPOSE: Primary Aim was to explore the impact of inhaled treprostinil sodium inhalation on ventilation perfusion matching when used in patients with group 1 PAH with concomitant COPD by measuring arterial blood gas (ABG) at the beginning and end of study. Secondary Aim was to explore the effects of inhaled treprostinil sodium on COPD related quality of life, 6MWD, PFT, WHO functional class, and the modified Borg dyspnea score at the end of the 6 MWT. METHODS: Patients with a diagnosis of PAH (defined as pulmonary artery mean pressure of ≥ 25 mm Hg and pulmonary artery wedge pressure or left ventricular end diastolic pressure of ≤ 15 mm Hg) who were being initiated on inhaled treprostinil and had concomitant COPD (defined as FEV1/FVC ratio ≤ 70% with FEV1 ≥ 40% predicted) were considered for inclusion in this pilot study. Other inclusion criteria were; age between 18 - 80 years and a baseline 6MWD ≥ 150 meters with no change in COPD treatment for at least 30 days prior to enrollment. Patients were excluded if they were treated with an endothelial receptor antagonist, phosphodiesterase inhibitor or parenteral prostanoids within 3 months prior to enrollment. Patients were assessed at baseline and weeks 4, 8, 12, and 16. Assessments included adverse events, physical exam, WHO functional class, 6MWT, modified Borg dyspnea score, and concomitant medication. At baseline and week 16 the following assessments were performed: SGRQ, ABG, and PFT. RESULTS: The median age was 65 years (range, 56-80) and 5 (56%) were male. Among the 9 patients, 6 (67%) had an increase in 6MWD from baseline to week 16 (Median change=19 meters). Only 3 of the 9 patients (33%) had an increase in A-a gradient from baseline to week 16 (Median change= -7). There was no evidence of difference in any of the arterial blood gases, WHO functional class, 6MWT results, or SGRQ scores from baseline to week 16. There was a statistically significant decline in several of the PFT measures, including FEV1 (Median change= -0.18 L, P=0.004; Median change=-7% of predicted, P=0.016), FVC (Median change=-0.23 L, P=0.027), and DLCO (Median change=-5% of predicted, P=0.023). None of the other PFT measures showed a statistically significant change from baseline to week 16. CONCLUSIONS: Inhaled treprostinil did not seem to adversely impact oxygenation in the majority of the study patients. CLINICAL IMPLICATIONS: It appears to be safe to further investigate use of inhaled treprostinil in patient with pulmonary hypertension and COPD. DISCLOSURE: Abubakr Bajwa: Grant monies (from industry related sources): UT investigator grant, Consultant fee, speaker bureau, advisory committee, etc.: UT, Gilead, Actelion Adil Shujaat: Grant monies (from industry related sources): UT investigator grant Minal Patel: Grant monies (from industry related sources): UT investigator grant Franck Rahaghi: Grant monies (from industry related sources): UT investigator grant, Consultant fee, speaker bureau, advisory committee, etc.: UT, Actelion, Gilead Colleen Thomas: Grant monies (from industry related sources): UT investigator grant Charles Burger: Grant monies (from industry related sources): UT investigator grant No Product/Research Disclosure Information