5. CONCLUSION
Although evidence from our results requires careful application to clinical decision making owing to several limitations inherent to spontaneous reporting databases, our approach using a spontaneous adverse event reporting database for survival analysis may provide useful information on treatment efficacies in limited situations such as the treatment of rare diseases. Among drugs targeting the prostacyclin pathway, epoprostenol was most associated with long-term survival in the PAH patients reported in the JADER database. ERAs, especially macitentan, were associated with improved prognosis compared with non-ERA users. In contrast, the effect of sildenafil on improvement in PAH mortality was not observed in our data, suggesting the relative superiority of tadalafil over sildenafil. Additionally, the long-term efficacy of anticoagulant therapy with warfarin was confirmed in only non-epoprostenol users.