A search in clinicaltrials.gov as of November 2022 renders at least three tetraspecific TCE: GNC-038 (CD3/41BB/PD-L1/CD19), being tested in phase 1 trials with patients with NHL (NCT04606433) and DLBCL (NCT05192486); GNC-035 (CD3/41BB/PD-L1/ROR1) in patients with breast cancer; and GNC-039 (CD3/41BB/PD-L1/EGFRvIII) in glioma (NCT05160545). Here, CD19 is linked to breast carcinoma.