In previously drug-naive IPAH patients we observed a reduction of plasmin-anti-plasmin levels after 3 months of treatment with PAH specific drugs, while tPA, D-Dimer, TAT, F1+2, PAI-1, and IL-6, ET-1 remained unchanged (Table 3, Figure 3). The gene discussed is SERPINE1; the disease is idiopathic pulmonary arterial hypertension.