Vildagliptin, a DPP‐4 inhibitor, has been shown to reduce pathological vasodilation and angiogenesis in the lungs of rats with HPS, with the underlying mechanism involving the improvement of hepatic and pulmonary levels of ET‐1, eNOS, iNOS and VEGF‐A [57]. The gene discussed is NOS2; the disease is Hermansky-Pudlak syndrome.