PDCD1 and mesothelioma: Moreover, recent research has shown that LMB‐100, an anti‐mesothelioma PE24, triggered a systemic inflammatory response in some patients, and improved progression‐free survival when combined with pembrolizumab, an antibody against programmed cell death 1 (PD‐1).[26] These findings collectively highlight a broader immunomodulatory role for PE immunotoxins in clinical settings.