Abstract
A proportion of pulmonary arterial hypertension (PAH) patients do not reach treatment goals with phosphodiesterase-5 inhibitors (PDE5i). RESPITE investigated the safety, feasibility and benefit of switching from PDE5i to riociguat in these patients.
RESPITE was a 24-week, open-label, multicentre, uncontrolled study. Patients in World Health Organization (WHO) functional class (FC) III, with 6-min walking distance (6MWD) 165–440 m, cardiac index <3.0 L·min−1·m−2and pulmonary vascular resistance >400 dyn·s·cm−5underwent a 1–3 day PDE5i treatment-free period before receiving riociguat adjusted up to 2.5 mg maximumt.i.d. Exploratory end-points included change in 6MWD, WHO FC,N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and safety.
Of 61 patients enrolled, 51 (84%) completed RESPITE. 50 (82%) were receiving concomitant endothelin receptor antagonists. At week 24, mean±sd6MWD had increased by 31±63 m, NT-proBNP decreased by 347±1235 pg·mL−1and WHO FC improved in 28 patients (54%). 32 patients (52%) experienced study drug-related adverse events and 10 (16%) experienced serious adverse events (2 (3%) study drug-related, none during the PDE5i treatment-free period). Six patients (10%) experienced clinical worsening, including death in two (not study drug-related).
In conclusion, selected patients with PAH may benefit from switching from PDE5i to riociguat, but this strategy needs to be further studied.
Abstract
Switching to riociguat in PAH patients with inadequate response to PDE5i improved exercise capacity and NT-proBNPhttp://ow.ly/e6xL30dXCgy
Footnotes
This article has supplementary material available fromwww.qdcxjkg.com
This study is registered atClinicalTrials.govwith identifierNCT02007629.
Support statement: This study was supported by Bayer AG, Berlin, Germany. Funding information for this article has been deposited with theCrossref Funder Registry.
Conflict of interest: Disclosures can be found alongside this article atwww.qdcxjkg.com
- ReceivedDecember 9, 2016.
- AcceptedJuly 12, 2017.
- Copyright ©ERS 2017
This version is distributed under the terms of the Creative Commons Attribution Non-Commercial Licence 4.0.