Bischofberger-helmed Kronos bags $105M to tackle tough targets

Kronos Bio CEO Norbert Bischofberger (Kronos Bio)

Kronos Bio has raised $105 million. The series A sets the Norbert Bischofberger-helmed biotech up to advance efforts to hit historically undruggable targets. 

Bischofberger, the former head of R&D at Gilead Sciences, took over as CEO of Kronos last year and set about advancing two lead preclinical projects using $18 million in seed funding. With those two programs advancing and work to identify drugs against tough oncology targets underway, Kronos returned to its investors to put together a big series A round. 

Omega Funds and Vida Ventures, an investment firm co-founded by ex-Kite Pharma CEO Arie Belldegrun, led the round with the support of  Nextech, GV, Perceptive Advisors, Invus and Polaris Partners. Bischofberger, former Gilead CEO John Martin and Belldegrun also participated.

The syndicate came together to support Kronos’ efforts to hit tough targets. To date, drug developers have addressed a subsection of proteins with structures that are amenable to drugging with small molecules. A far larger pool of proteins lack obvious pockets for small molecules to bind to. 

Kronos intends to overcome that structural barrier by performing high-throughput screens against target proteins in conditions designed to be more physiologically relevant. In doing so, Kronos thinks it can identify small molecules capable of interfering with the biology of proteins previously thought to be undruggable.

The screening platform has uncovered candidates involving MYC and cyclin-dependent kinase 9. Those programs are moving through preclinical. In parallel, Kronos is working to discover drugs related to other transcription factors, oncoproteins and novel E3 ligases.

Kronos will use some of the series A money to take on more staff at its offices in Boston and San Francisco. Through the additions, Kronos aims to equip itself to take a tilt at an ambitious goal.

“We seek to challenge the historic belief that certain targets cannot be pursued. Our goal is to unlock new therapeutic approaches and bring treatments to areas with high unmet need,” Bischofberger said in a statement.