Startup gets $21M for monoclonal antibody that reaches inside the cancer cell

Most human monoclonal antibody therapies target proteins on the outer membrane of the cell – but a Bay Area startup is receiving a healthy flush of cash to further investigate its drug that reaches cancer cells on the inside. Cancer immunotherapy player Eureka Therapeutics has raised $21 million in a Series C financing round, led by […]

Most human monoclonal antibody therapies target proteins on the outer membrane of the cell – but a Bay Area startup is receiving a healthy flush of cash to further investigate its drug that reaches cancer cells on the inside.

Cancer immunotherapy player Eureka Therapeutics has raised $21 million in a Series C financing round, led by new investor Yuan Capital, a China-based venture capital firm.

Much like many other cancer immunotherapy biotechs, Bay Area-based Eureka develops antibodies engineered to mimic a T cell receptor, recognizing the proteins inside cancer cells and galvanizing a patient’s immune system to attack and destroy the cancer cell.

About 90 percent of cancer-specific targets are intracellular proteins, Eureka says, but traditional monoclonal antibodies in humans have only been able to target proteins found on the outside of cancer cells. The company continues:

Because of this, intracellular proteins have long been considered “undruggable” by small molecule or conventional monoclonal antibody drug approaches.

As proteins inside the cell get broken down as part of regular cellular processes, fragments of those proteins (peptides) are carried to the cell surface by MHC (major histocompatibility complex) molecules. When T cells (a key component of the immune system) recognize these fragments as abnormal, they kill the diseased cell.

The company signed a license agreement earlier this year with Novartis to develop and commercialize ESK1, a preclinical monoclonal antibody that treats leukemia and other cancers. That antibody, which was co-developed by Eureka and Memorial Sloan-Kettering Cancer Center, targets intracellular protein WT1.