PDCD1 and mesothelioma: Targeting LAG-3 is an active area of investigation in the treatment of mesothelioma; the bispecific molecule tebotelimab, which targets PD-1 and LAG-3, was studied in a phase 1 trial of patients with both solid tumors and hematologic cancers, including mesothelioma, and was found to be safe and warrants further investigation [61].