Fidasimtamab  (Synonyms: IBI-315; BH2950)

Fidasimtamab is a bispecific antibody targeting human epidermal growth factor receptor 2 (Her2) and programmed death protein 1 (PD-1), with a K_a of 3.55e-10 M for human Her2 and a K_a of 1.17e-9 M for human PD-1. Fidasimtamab cross-links Her2-positive tumor cells with PD-1-positive T cells to form immune synapses, blocks PD-1-ligand interactions, preserves antibody-dependent cellular cytotoxicity, induces gasdermin B (GSDMB)-mediated pyroptosis, and activates T cells. Fidasimtamab is applicable to relevant research on Her2-positive gastric cancer^[1].

Human IgG1 kappa

Human IgG1 kappa, Isotype Control

Human

ERBB2 & PDCD1

Fidasimtamab binds to purified human PD-1 and Her2 proteins with high affinity, with K_D values of 1.17 × 10^-9 M and 3.55 × 10^-10 M, respectively^[1].
Fidasimtamab (600 nM; 30 min at 4 °C) induces a 24.10% association rate between N87 gastric cancer cells and activated human T cells^[1].
Fidasimtamab (serial dilutions; 3 d) dose-dependently activates human CD4⁺ T cells in an MLR assay, inducing secretion of IFNγ and IL-2 with potency comparable to the parental anti-PD-1 antibody^[1].
Fidasimtamab (600 nM; 24 h) significantly enhances T cell-mediated cytotoxicity against N87 and SNU-216 Her2-positive gastric cancer cells, as measured by increased LDH release^[1].
Fidasimtamab (600 nM; 6 h) induces pyroptosis in N87 and SNU-216 Her2-positive gastric cancer cells in the presence of activated T cells, and increases IL-18 secretion by 24 h, via cleavage of GSDMB to its active N-terminal fragment^[1].
Fidasimtamab (serial dilutions; 4 h at 37 °C) exhibits potent ADCC activity against N87 Her2-positive gastric cancer cells when incubated with human NK cells^[1].
Fidasimtamab (600 nM; 24 h) induces a 2-3 fold increase in cell death in PDXO-1 Her2-positive gastric cancer organoids in the presence of T cells, and promotes association between T cells and organoids^[1].
Conditioned media from Her2-positive gastric cancer cell-T cell cocultures treated with Fidasimtamab (600 nM; 24 h) activates human CD8⁺ T cells, increasing CD25 expression and enhancing IFNγ secretion^[1].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Fidasimtamab (IBI-315/BH2950) (5 mg/kg; i.p.; every 3 days; 2 weeks) achieves a 116.8% tumor inhibition rate in human PBMC-reconstituted NOG mice bearing N87 Her2-positive gastric cancer, with enhanced intratumoral T cell infiltration^[1].
Fidasimtamab (IBI-315/BH2950) (5 mg/kg; i.p.; every 3 days; 2 weeks) achieves a 77% tumor volume reduction in human PBMC-reconstituted NOG mice bearing PDX-1 Her2-positive gastric cancer, with enhanced intratumoral T cell infiltration, activation, and proliferation^[1].
Fidasimtamab (IBI-315/BH2950) (5 mg/kg; i.p.; every 3 days; 2 weeks) loses its significant tumor inhibitory activity in human PBMC-reconstituted NOG mice bearing GSDMB-knockdown N87 Her2-positive gastric cancer, confirming dependency on GSDMB-mediated pyroptosis^[1].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

2064  [NCBI] & 5133  [NCBI]

P04626 & Q15116

ELISA, FACS, Functional assay

Unconjugated

The product can be reconstituted/diluted with sterile PBS or saline.

144.62 kDa

2377419-89-9

Liquid

Colorless to light yellow

[Fidasimtamab]

Shipping with dry ice.

Please refer to the lot-specific COA for specific buffer information.

Please store the product under the recommended conditions in the Certificate of Analysis.

• 
  Human IgG1 kappa

• [1]. Lin W, et al. Anti-PD-1/Her2 Bispecific Antibody IBI315 Enhances the Treatment Effect of Her2-Positive Gastric Cancer through Gasdermin B-Cleavage Induced Pyroptosis. Adv Sci (Weinh). 2023;10(30):e2303908.  [Content Brief]