Aspyrian Therapeutics Raises $8.5M for New Tumor Immunotherapy

Xconomy San Diego — 

[Updated 2/4/15 12:15 pm. See below.] See below.San Diego-based Aspyrian Therapeutics, founded in 2010 to advance technology that uses near-infrared light to activate an immune response targeting certain types of tumors, has raised almost $8.5 million from investors, according to a recent SEC filing. The investors were not identified.

The technology was developed at the National Cancer Institute (NCI) by Hisataka Kobayashi and Peter Choyke, the scientific leaders of the NCI’s molecular imaging program. Their approach uses near-infrared light to activate a toxic dye attached to monoclonal antibodies that bind to the surface of certain tumor cells. The concept is promising because the treatment is highly specific to cancer cells with epidermal growth factor receptors (EGFRs), and because the near-infrared light has caused no detectible phototoxic effect among antibody-dye conjugates that are not bound to the surface of cancer cells.

[Updated 2/4/15] In an e-mail, Aspyrian CEO M. Scott Salka explains the dye attached to the antibody is not toxic until it is activatated. He writes: “The dye we use is actually non-toxic and very water soluble. The killing effect is a very local phenomenon around the dye molecules that only occurs when they are being excited by a 690 nm (near infrared) light source. Since the dye itself is so water soluble (lipophobic), it has no affinity itself for normal tissues and cells, which is where the antibody comes into play; the monoclonal antibody selectively carries the dye payload to cells expressing the EGFR antigen, giving us a very large therapeutic window between normal epithelial cells (which do express some level of EGFR) and the cancer cells (which express a very high number of EGF receptors).”

Aspyrian secured an exclusive license for the technology. According to the company’s website, Aspyrian plans to obtain early stage clinical data by the end of this year that demonstrates the safety of its technology as well as an anti-cancer response in humans.