In vitro cytokine release with immobilized or soluble antibody similar to negative control; cytokine release unlikely
“In an in vitro assay using human blood, the cytokine release profile for immobilized and soluble toripalimab was similar to that of the negative control, indicating that toripalimab is unlikely to induce cytokine release.”
✓ VerifiedFDA multi-discipline review, p. 98Source ↗
Biodistribution & persistence
Human TCR: expected staining of PD-1-expressing mononuclear cells; no unexpected tissue cross-reactivity
“This staining was expected based on PD-1 expression in mononuclear cell types, including T cells, B cells, and other myeloid cells. No unexpected tissue cross-reactivity was observed.”
✓ VerifiedFDA multi-discipline review, p. 98Source ↗
Modality-specific risk
Increased susceptibility to pathogens such as tuberculosis from loss of PD-1 function
“While loss of PD-1 function enhances clearance of some tumors and viral infections, it increases susceptibility to certain other pathogens such as tuberculosis in some animal models.”
✓ VerifiedFDA multi-discipline review, p. 98Source ↗
Anti-drug antibodies: animals
ADA reduced toripalimab exposure and receptor occupancy in monkeys; no ADA-mediated toxicity
“Decreased in toripalimab exposure and receptor occupancy correlated with the formation of ADA. There were no ADA-mediated toxicity findings.”
3.4% treatment-emergent ADA (240 mg Q3W with chemotherapy, JUPITER-02)
“Of the 146 evaluable patients in JUPITER-02 with nasopharyngeal cancer who received LOQTORZI 240 mg every 3 weeks for a median duration of 15.1 months, in combination with gemcitabine and cisplatin, 3.4% tested positive for treatment-emergent ADA.”
In vitro whole-blood cytokine release far below alemtuzumab/TGN1412 controls; no effects on monkey TDAR, lymphocyte subsets or serum cytokines; ADA in some monkeys