Kronos Bio Reels In $105M for Drugs That Hit “Undruggable” Targets

Xconomy San Francisco — 

Kronos Bio has raised $105 million in financing to develop therapies intended to target disease-causing proteins that have so far eluded the best efforts of drug hunters.

The Series A round of funding announced Thursday was led by Vida Ventures and Omega Funds.

Drugs typically work by either binding to a target site on a molecule or blocking it. But San Mateo, CA-based Kronos notes that most of the currently available therapies address the minority of the proteins in the body—those that can be targeted by traditional small molecule drugs. Most of the body’s proteins are considered “undruggable” because they don’t have firm structures or known binding sites that a drug can hit.

Kronos, which is led by CEO Norbert Bischofberger, the former chief scientific officer of Gilead Sciences (NASDAQ: GILD) says its technology screens chemical libraries against target proteins to identify small molecules that can hit molecular targets historically thought of as undruggable. The technology, called Small Molecule Microarray, is based on the research of MIT Professor Angela Koehler, the scientific founder of Kronos. The company says the technology can find drugs that work by a number of mechanisms, including by directly disrupting protein-protein interaction or protein-DNA interactions. The company says its drugs could also take an indirect approach to hitting to a disease-causing protein by targeting cofactors, which are the chemicals that assist enzymes.

In a prepared statement, Bischofberger said the fresh capital will help Kronos advance development of two preclinical compounds that are based on the company’s technology. One of the two most advanced compounds listed on the Kronos website targets a cofactor related to the androgen receptor. Such cofactors have been studied as potential targets for prostate cancer drugs. The second of the most advanced Kronos compounds targets cyclin-dependent kinase 9, a protein that has been studied as a drug target for ovarian cancer. The company also plans to use the new cash to expand its headcount in Cambridge, MA, where it has a research site, and at its headquarters in San Mateo.

Other investors in the Kronos financing included Nextech, GV, Perceptive Advisors, Invus, and Polaris Partners. The company said Bischofberger as well as members of the board of directors also invested. In conjunction with the financing, Nextech partner Jakob Loven is joining the Kronos board.

Photo by Flickr user Celine Nadeau via a Creative Commons license