Mechanism of Action

Important information about Zytorvi^®:

• Humanized monoclonal antibody IgG4^{^} that exhibits high binding affinity to PD-1;¹

• It binds to the FG loop of PD-1 with a long, unconventional HCDR3 distinct from other approved immunotherapies;^1,2

• It has high affinity and slow dissociation with PD-1, compared to pembrolizumab and nivolumab.³

IgG4^{^} = Immunoglobulin G4; PD-1 = Programmed Cell Death 1; HCDR3 = Heavy Chain Complementarity Determining Region 3.

References

1. Rajasekaran N, Ravindranathan S, Wang X, Chin DJ, Tseng SY, Klakamp S, Widmann K, Young G, Yu B, Kapoor V, Vexler V. Toripalimab: A Next-Generation Anti-PD-1 Antibody for Treatment of Nasopharyngeal Carcinoma. International Journal of Radiation Oncology, Biology, Physics. 2024 Apr 1;118(5):e88-9.

2. Mai HQ, Chen QY, Chen D, et al. Toripalimab or placebo plus chemotherapy as first-line treatment in advanced nasopharyngeal carcinoma: a multicenter randomized phase 3 clinical trial. Nat Med. 2021;27(9):1536-1543. doi:10.1038/s41591-021-01444-0.

3. Fu J, et al. Acta Pharmacol Sin. May 2017; 38(5): 710-718.