Safety and effectiveness of riociguat for chronic thromboembolic pulmonary hypertension in real-world clinical practice: interim data from post-marketing surveillance in Japan

This multicenter, prospective, non-interventional study (ClinicalTrials.gov: NCT02117791) evaluated the safety and effectiveness of riociguat for chronic thromboembolic pulmonary hypertension in Japanese clinical practice, registering all patients with chronic thromboembolic pulmonary hypertension treated with riociguat following its launch in Japan in April 2014. Safety was assessed by analyzing the adverse drug reactions. Effectiveness measurements included the assessment of change in World Health Organization functional class, six-minute walk test, and hemodynamics. Overall, 1031 patients were included in the safety analysis with 811 (78.7%) patients in World Health Organization functional class II/III. The mean treatment duration was 591.4 days (median 441.0 days). Adverse drug reactions were reported in 19.5% of patients, the most common being hypotension (5.9%), headache (3.0%), dizziness (1.9%), and gastroesophageal reflux disease (1.5%). Serious adverse drug reactions were reported in 2.1% of patients. Estimated survival was 97.0% at one year, 95.8% at two years, and 94.4% at three years. The effectiveness analysis (n=1027) showed significant increases from baseline in six-minute walking distance, and significant reductions from baseline in mean pulmonary arterial pressure and pulmonary vascular resistance. These interim results of riociguat in Japanese patients with chronic thromboembolic pulmonary hypertension demonstrated a safety profile that was generally consistent with those of pivotal clinical studies. The study is ongoing, and will continue to provide insights into the safety and effectiveness of riociguat in real-world practice.