Conference: 2010 International PHA Conference and Scientific Sessions
Release Date: 06.24.2010
Presentation Type: Abstracts
Hoeper MM1, Halank M2, Wilkens H3, Günther A4, Weimann G5, Gebert I5, Leuchte H6, Behr J6.
1. Hannover Medical School, Hannover, Germany
2. Dresden University, Dresden, Germany
3. University of the Saarland, Saarbrücken, Germany
4. Giessen University, Giessen, Germany
5. Bayer Healthcare, Berlin, Germany
6. University of Munich, Grosshadern, Germany
BACKGROUND: The development of pulmonary hypertension (PH) is a common problem in patients with interstitial lung disease (ILD) and its occurrence is associated with greater functional impairment and decreased survival. To date, no treatment has been shown to improve exercise capacity or outcome in patients with pulmonary hypertension associated with ILD (PH-ILD). Riociguat, a stimulator of soluble guanylate cyclase (sGC), is a novel drug currently under study for several forms of PH. We present the results of the first pilot study assessing the safety and preliminary efficacy of riociguat in patients with PH-ILD.
METHODS: In this open-label, uncontrolled trial, 21 patients (62% male; age 60±15 years; mean total lung capacity 67±12% of the predicted value) with PH-ILD received riociguat at a dose of up to 2.5 mg t.i.d. over a period of 12 weeks. The predominant underlying disease was usual interstitial pneumonia (n=13); other forms of ILD were less common (non-specific interstitial pneumonia, n=4; sarcoidosis, n=3; systemic sclerosis, n=1).
RESULTS: Riociguat was well tolerated by the majority of patients. 17 patients completed the study while 4 patients discontinued prematurely, two of them because of side effects possibly related to study medication (1 case each of gastroenteritis and syncope, respectively). Riociguat therapy resulted* in an increase in cardiac output from 4.3±1.4 L/min at baseline to 5.6±1.8 L/min after 12 weeks of therapy. The mean pulmonary artery pressure (PAPm) increased slightly (40±10 mmHg at baseline vs 42±6 mmHg, whereas the pulmonary vascular resistance (PVR) dropped from 659±205 dyn.s.cm-5 to 537±186 dyn.s.cm-5. The arterial oxygen saturation (SaO2) declined from 93±4% to 91±7%, whereas the mixed-venous oxygen saturation (SvO2) increased from 63±13% to 68±6%. Functional class remained unchanged. The 6 min walk distance increased slightly from 321±95 m at baseline (n=21) to 342±113 m after 12 weeks (n=17).
CONCLUSIONS: In this pilot trial riociguat was well-tolerated, which provides preliminary evidence that riociguat may be safe in patients with PH-ILD. A slight improvement in 6MWD at 12 weeks and a considerable increase in cardiac output and reduction in PVR could be observed. Data from large controlled studies are warranted to prove safety and efficacy of riociguat in patients with PH-ILD.
*descriptive summary statistics - safety analysis
Originally presented at the American Thoracic Society 2010 Annual Meeting. Funded by Bayer Healthcare.