Eleven Biotherapeutics

Proxinium™ (VB4-847):
Recombinant fusion protein in clinical development for the treatment of late-stage squamous cell carcinoma of the head and neck

Proxinium is a product candidate based on Eleven’s Targeted Protein Therapeutics (TPT) platform. Proxinium consists of a single chain EpCAM (epithelial cell adhesion molecule) antibody fragment fused with a potent cytotoxin, designed to be an optimized therapeutic for local tumor administration (via intratumoral injection) for the treatment of squamous cell carcinoma of the head and neck. To date, Proxinium has been tested in over 150 patients, including Phase I and II clinical trials.

As with Eleven’s other TPTs, Proxinium is designed to target cancer cells expressing EpCAM, which internalize the TPT once it is bound. Within the cell, the payload dissociates from the single chain fragment and is then able to exert its cell-killing activity. In addition, Proxinium-induced apoptosis is believed to set off a chain of events that may lead to stimulation of the patient’s own immune response against cancer cells.