Birinapant

Description

Birinapant is a bivalent mimetic of the Diablo homolog known as second mitochondria-derived activator of caspase (Smac). It is an antagonist of cellular inhibitor of apoptosis 1 (cIAP1, or BIRC2), cIAP2 (BIRC3), and XIAP (BIRC4), binding each at nanomolar concentrations. Birinapant causes rapid cIAP1 degradation, caspase activation, PARP cleavage, and NF-κB activation in breast cancer cells. It shows in vivo antitumor activity, inducing apoptosis in several types of cancer xenografts in mice.

Description

Birinapant is a developmental drug that is designed to restore the apoptosis functionality (programmed cell death) to cancer cells. The unusual dimeric molecule?inhibits proteins that block apoptosis. TetraLogic Pharmaceuticals in Malvern, PA, is currently in early phase II clinical trials for using birinapant in leukemia, pancreatic cancer, and ovarian cancer patients.

The Uses of Birinapant

Birinapant is a bivalent SMAC mimetic compound antagonist of TRAF2 associated cIAP1 and cIAP2.

Definition

ChEBI: Birinapant is a dipeptide.

Enzyme inhibitor

This rotationally symmetric SMAC mimetic antagonist and anticancer agent (FW = 806.94 g/mol; CAS 1260251-31-7) targets cellular Inhibitor of Apoptosis Protein (or cIAP1; Kd of <1 nM), arguably the most potent mammalian caspase inhibitor, showing single-agent efficacy due to its panIAP antagonism and causing rapid cIAP1 degradation, caspase activation, PARP cleavage, and NF-κB activation. When administered in combination with TNF-α, Birinapant is effective against a melanoma cell line with acquired resistance to BRAF inhibitors