There are reports of clinical improvement of PAH with immunosuppressive therapy, and advanced therapy inclusive of endothelin receptor blockers, prostanoids, and phosphodiesterase-5 inhibitors have been associated with improvement in exercise tolerance and pulmonary hemodynamics.1 IL-1 receptor antagonists (anakinra) has been reported to cause rapid regression of disease.10 IL-6 inhibitor use (tocilizumab) has been proposed for AOSD based on the disease pathology. Here, IL6 is linked to adult-onset Still disease.