PAH-specific therapy: ERA: 84.9% (PH-ILD) vs. 72.6% (PAH), PDE5 inhibitors: 10.6% (PH-ILD) vs. 14.5% (PAH), Prostacyclin analogs: 3.0% (PH-ILD) vs. 1.6% (PAH), Sequential oral combination therapy in 15 (PH-ILD) and 22 (PAH) patients. Immunosuppressive therapy was administered, particularly in PH-ILD. This evidence concerns the gene PDE5A and interstitial lung disease.