Pasritamig  (Synonyms: JNJ-78278343; KLCB-245)

Pasritamig (JNJ-78278343; KLCB-245) is a bispecific T-cell engager (BiTE) that targets the complex of human kallikrein KLK2 and CD3 receptor. Pasritamig redirects the cytotoxicity of T cells to KLK2-expressing tumor cells and induces T cell-mediated lysis of KLK2-expressing prostate cancer cells. Administered via subcutaneous injection, subcutaneous infusion or intravenous infusion, Pasritamig exhibits antitumor activity against metastatic castration-resistant prostate cancer. Pasritamig has a safety profile with an extremely low incidence of cytokine release syndrome and can be safely administered in an outpatient setting. Pasritamig is applicable to the research of metastatic castration-resistant prostate cancer^[1][2][3][4].

(H-gamma1_L-kappa)_scFvkh-G1(h-CH2-CH3)

Human IgG1 kappa, Isotype Control

Human

KLK2 & CD3E

At subcutaneous injection doses of 0.5~2000 μg/mL and intravenous injection doses of 150~900 μg/mL, Pasritamig exhibits linear and non-linear (KLK2-mediated) elimination in an open two-compartment model, with a terminal half-life of 18.3 days, and its exposure increases in an approximately dose-proportional manner^[2].

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

3817  [NCBI] & 916  [NCBI]

P20151 & P07766

ELISA, FACS, Functional assay

Unconjugated

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

124.81 kDa

2921676-04-0

Liquid

Colorless to light yellow

[Pasritamig]

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.

• 
  G1-kappa_scFv-h-CH2-CH3

• 
  Immobilized Kallikrein-2 Protein, Human (HEK293, His, HY-P70317) can bind Pasritamig. The EC₅₀ for this effect is 53.53 ng/mL.
• 
  Immobilized CD3 epsilon Protein, Human (HEK293, His,HY-P70506) can bind Pasritamig. The EC₅₀ for this effect is 791.3 ng/mL.
• 
  Flow cytometric analysis of 1X10⁶ Juakat cells with Pasritamig (HY-P991015, red). Cells were fixed with 4% paraformaldehyde. Then stained with the primary antibody at 1/200 dilution for an hour at 4℃. AF 488-conjugated AffiniPure Goat Anti-Human IgG H&L (HY-P83776) was used as the secondary antibody at 1/1,000 dilution for 30 minutes at 4℃. Human IgG1 kappa (HY-P99001, blue) was used as the isotype control, cells without incubation with primary antibody were used as the unlabeled control (black).

• [1]. Stein MN, et al. Pasritamig, a First-in-Class, Bispecific T-Cell Engager Targeting Human Kallikrein 2, in Metastatic Castration-Resistant Prostate Cancer: A Phase I Study. J Clin Oncol. 2025;43(22):2515-2526.  [Content Brief]

  [2]. Cui J, et al. 298eP Preliminary results of a multicenter, open-label, randomized, phase II trial (ALTER-PA-001 trial) of anlotinib and benmelstobart in combination with AG versus AG as first-line treatment for metastatic pancreatic cancer[J]. Immuno-Oncology and Technology, 2025, 28.

  [3]. Meng L, Yang Y, Mortazavi A, Zhang J. Emerging Immunotherapy Approaches for Treating Prostate Cancer. Int J Mol Sci. 2023 Sep 20;24(18):14347.  [Content Brief]

  [4]. Wang X, et al. 305eP Camrelizumab combined with nab-paclitaxel as second-line therapy for advanced biliary tract cancer (BTC): A real-world study[J]. Immuno-Oncology and Technology, 2025, 28.