Cinrebafusp alfa  (Synonyms: PRS 343)

Cinrebafusp alfa (PRS 343) is a high affinity CD137/HER2 bispecfic anticalin-based drug. Cinrebafusp alfa binds to recombinant human HER2 (K_d=0.3 nM) and human monomeric CD137 (4-1BB; K_d=5 nM). Cinrebafusp alfa facilitates T-cell costimulation by tumor-localized, HER2-dependent 4-1BB clustering and activation, further enhancing T-cell receptor-mediated activity and leading to tumor destruction. Cinrebafusp alfa has the potential for HER2+ solid tumors research^[1][2].

Human IgG4 kappa

Human IgG4 (S228P) kappa, Isotype Control

Fusion Protein

Cinrebafusp alfa (PRS 343) binds HER2-expressing MCF-7 cells with an EC₅₀ of 7.4 nmol/L and binds to CHO cells transfected with human 4-1BB with an EC₅₀ of 6.2 nmol/L in a FACS assay^[1].

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

Cinrebafusp alfa (PRS 343; 0.2-10 mg/kg; IV; once weekly; for 20 day) leads to tumor growth inhibition and has a dose-dependent increase of tumor-infiltrating lymphocytes in a humanized mouse model engrafted with HER2-positive SK-OV-3 tumor cells^[1].
Cinrebafusp alfa (10 mg/kg; IV; single dose) has the terminal elimination half-life of >14 days in male CD-1 mice. Cinrebafusp alfa (3 mg/kg; IV; single dose) has the terminal elimination half-life approximately 4 days in male cynomolgus monkeys^[1].

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

2218515-90-1

Liquid

Colorless to light yellow

[Cinrebafusp alfa]

Shipping with dry ice.

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

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  Human IgG4 kappa

• 
  Immobilized Cinrebafusp alfa can bind Human 4-1BB/CD137 Protein (ECD, His Tag). The EC₅₀ for this effect is 1.33 ng/mL.
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  Immobilized Cinrebafusp alfa can bind Human Her2/ERBB2 Protein (ECD, His Tag). The EC₅₀ for this effect is 1.66 ng/mL.

• [1]. Marlon J Hinner, et al. Tumor-Localized Costimulatory T-Cell Engagement by the 4-1BB/HER2 Bispecific Antibody-Anticalin Fusion PRS-343. Clin Cancer Res. 2019 Oct 1;25(19):5878-5889.  [Content Brief]

  [2]. G. Ku, et al. 525O A phase I dose escalation study of PRS-343, a HER2/4-1BB bispecific molecule, in patients with HER2-positive malignancies. ABSTRACT ONLY, VOLUME 31, SUPPLEMENT 4, S462-S463, SEPTEMBER 01, 2020.