CAR‐T cells against fibroblast activation protein α (FAP) have entered clinical trials (NCT01722149), though concerns remain.[34] To improve safety and efficacy, bispecific CAR‐T cells targeting both FAP and tumor antigens (e.g., glypican 3 (GPC3) or mesothelin (MSLN)) have shown promise in preclinical models (Figure 2BIII).[35, 36]. Here, MSLN is linked to neoplasm.