Can Stemcentrx thrive as a biotech killing cancer stem cells?


Stemcentrx scientists working with targeted molecules that can kill some types of lung cancer. MIT Tech Review Image.

A stem cell biotech in the news this week was one that had mostly flown under the radar previously.

Stemcentrx has a focus on killing cancer stem cells as a novel approach to treating cancer. Antonio Regalado had a nice article yesterday on the company. He reports that Stemcentrx has around a half a billion in funding. It is valued in the billions. These are very unusual figures for a stem cell biotech.

Stemcentrx is developing novel cancer therapeutics such as antibodies that target cancer stem cells. Their development pipeline at least in part uses a model of serial xenograft tumor transplantation in mice. Cancer stem cells are also sometimes called “tumor initiating cells” (TIC). As a cancer stem cell researcher myself, I find Stemcentrx intriguing.

The company published an encouraging bit of preclinical data recently in Science Translational Medicine with a team of authors including leading company scientist, Scott Dylla. In this paper the team presented evidence that they have a product in the form of a loaded antibody (conjugated to a toxin) against a molecule called DLL3 important to TIC biological function and survival. DLL3 is part of the Notch signaling pathway. Stay tuned tomorrow for my interview with Dr. Dylla.

They showed that this anti-DLL3 antibody, SC16LD6.5, exhibited anti-tumor activities in xenograft models of pulmonary neuroendocrine tumors such as small cell lung cancer. The company also has a clinical trial ongoing but not currently recruiting using this drug, and they have another trial for ovarian cancer based on antibody targeting as well.

SC16LD6.5 also exhibited some degree of toxicity in rats and a non-human primate model so that’s a possible issue moving forward, but the toxic effects were at least partially reversible and when you’re dealing with a deadly disease some toxicity for treatment is kind of to be expected.

Can Stemcentrx survive and hopefully even thrive as a company selling products that kill cancer stem cells? We’ll have a clearer picture on this in a few years, but in general biotechs of this type in this arena have a high failure rate. We need to keep in mind the long, sobering path ahead between these kinds of preclinical result and getting an approved drug to patients.

At the same time, this team has the money and talent to potentially succeed, and again, there’s that half a billion in funding, which all by itself makes this stem cell biotech no ordinary company. There’s another unique thing going on here: famed tech investor Peter Thiel is one of the major funders of the company.

Those of us in the cancer stem cell field have long been engaged in the debate over whether these special cells exist in specific solid tumors and their functions in tumorigenesis. I believe they are present and important in some, but not all of such tumors. The controversial nature of TICs in lung cancer specifically makes SC16LD6.5 a high-risk, high reward kind of product.

More weapons against lung cancer will be of course a good thing and targeting cancer stem cells is an innovative approach.  The company is recruiting for many positions including scientists so if you are interested take a look.

I hope Stemcentrx succeeds and I look forward to reading more of their work as the years go by.