Aiming At P53, Cancer’s Hard Target, PMV Pharma Raises $74M

Xconomy New York — 

PMV Pharmaceuticals is the latest startup to load up with cash in an attempt to home in on one of the toughest targets in cancer biology: the tumor suppressor protein known as p53.

The company, headquartered in Cranbury, NJ, disclosed this morning that it has raised a $74 million Series B round from Topspin Biotech Fund, Euclidian Capital, InterWest Partners, OrbiMed Advisors, and Osage University Partners. PMV raised a $30 million Series A in 2014. The new cash will help PMV push into human clinical studies, though in its statement the startup didn’t say when those studies might begin.

PMV wants to treat cancer with small molecule drugs that protect a protein called p53. When p53 is functioning normally, it senses when a cell is dividing too fast and orders the cell to commit suicide. Its role as a cell’s first line of defense against cancer is why it’s often referred to as the “guardian of the genome.”

But in every type of cancer, p53 is shut down in one way or another; perhaps through a mutation of the p53 gene, perhaps because another gene is overriding the p53 signal. When p53 is nullified, cells rapidly replicate and form tumors in tissue or blood. A drug that protects p53 or restores its function could potentially have an impact on a broad range of cancers, which makes it tantalizing to drug makers.

So far, despite dozens of efforts, no one has brought a p53 drug to market. Still, drugmakers are trying. This Science article from 2016 highlights the different ways some of the newer startups, like San Diego-based Actavalon and Cleveland-based Z53 Therapeutics, are developing  p53-related cancer drugs. Cambridge, MA-based Aileron Therapeutics is in the mix as well; shows two different early-stage trials underway for its experimental drug, ALRN-6924.

Like many of its peers, PMV wants to restore the function of mutated p53 with a drug, though it didn’t disclose exactly what its approach will be. The company was co-founded by Arnold Levine, a molecular biologist at the Institute for Advanced Study in Princeton, NJ, who helped discover p53 in 1979; Princeton University virologist Thomas Shenk; and CEO David Mack, former general partner at Alta Partners.

Here’s more on p53 and the problems drug makers have encountered when going after it.