Simlukafusp alfa (FAP-IL2v) is an immunocytokine comprising an antibody against fibroblast activation protein α (FAPα) and an IL-2 variant that only binds IL-2Rβγ. Isotype: human IgG1.
Simlukafusp alfa (FAP-IL2v) shows binding affinity constants of 43±9 pM, 80±20 pM, 660±80 pM, 0.3 nM, 0.23 nM and 0.5 nM with huIL-2Rβγ, cyIL-2Rβγ, muIL-2Rβγ, huFAP, cyFAP and muFAP, respectively[1].Simlukafusp alfa (0-100 nM; 5 days) activates CD4+/CD8+ T cells and NK cells in vitro, but not preferentially Tregs[1].Simlukafusp alfa (0-100 nM) enhances Cetuximab -mediated antibody-dependent cellular cytotoxicity (ADCC) and Cibisatamab -mediated T-cell-dependent cellular cytotoxicity (TDCC) in vitro[1].
Simlukafusp alfa (FAP-IL2v) (1 mg/kg; i.v.; weekly for 4 weeks) is efficacious in combination with therapeutic antibodies in murine models of human cancer[1].
References:
[1]. Waldhauer I, et al. Simlukafusp alfa (FAP-IL2v) immunocytokine is a versatile combination partner for cancer immunotherapy. MAbs. 2021 Jan-Dec;13(1):1913791.