The Optimizing Immunosuppression for Steroid-Refractory Anti-PD-1/PD-L1 Pneumonitis trial (NCT04438382) is a phase II, open-label, randomised, interventional trial to optimise immunosuppression for steroid-refractory anti-PD-1/PD-L1 pneumonitis by studying the comparative effects of infliximab and intravenous immunoglobulin (Table 1). The gene discussed is CD274; the disease is pneumonitis.