Having Scoured the Ocean for Cancer Drugs, Nereus Aims to Prove Its Concept Works

Off the coast of the Bahamas, in sea grass more than a half-mile deep, San Diego-based Nereus Pharmaceuticals found a fungus that may be the key ingredient for an innovative new cancer drug. This will be a key year for gathering evidence that will either support or debunk the idea.

I got the download on Nereus last week in a conversation with co-founder and CEO Kobi Sethna and Charles White, the company’s chief business officer. Nereus has raised a whopping $125 million in venture capital in almost a decade of business, from big name investors like Roche Venture Fund, Alta Partners, and San Diego-based Forward Ventures, among others, so I figured it was worth taking a look.

The company is built on the idea that many of the biggest pharmaceutical breakthroughs, like penicillin, come from natural microbes. The bulk of these fungi and bacteria that led to drugs come from land, but, of course, Mother Nature has plenty of more biodiversity in the ocean. After years of sailing expeditions that trawled up potential drug candidates in hot and cold water, shallow and deep, from the Pacific and the Atlantic, Nereus has looked at hundreds of candidates for treating autoimmune disease and cancer—and now has settled on two lead horses against cancer that it thinks have a real shot. So the sailing expeditions are over, and now it’s time to push through the hard, unpredictable slog of clinical trials to see if these drugs really work in people.

“In this business, you’ve got to be focused. It’s the name of the game,” Sethna says. “We’ve morphed into an oncology company.”

So what does Nereus have to show for all that investment? The lead candidate (the one found off the coast of the Bahamas) is called NPI-2358. It’s a small-molecule drug synthesized in the lab to be similar in structure to a unique fungus it found in the ocean. This drug is designed to be a “vascular disrupting agent” to tumors. It’s made to attack existing blood vessels in tumors, unlike big-name cancer drugs like Genentech’s bevacizumab (Avastin) or Pfizer’s sunitinib (Sutent) that are meant to block the formation of new blood vessels to tumors, White says.

The reason the Nereus drug is still alive in the clinic is that it showed a long-lasting, potent ability to disrupt tumor blood flow, without causing the heart damage that has plagued other vascular-disrupting drugs in the class, White says. The first clinical trials supported further testing, confirming the drug wasn’t harming the heart while shrinking tumors at least partially for about three-fourths of patients when given in combination with Sanofi-Aventis’ docetaxel (Taxotere).

This molecule is in competition with

Author: Luke Timmerman

Luke is an award-winning journalist specializing in life sciences. He has served as national biotechnology editor for Xconomy and national biotechnology reporter for Bloomberg News. Luke got started covering life sciences at The Seattle Times, where he was the lead reporter on an investigation of doctors who leaked confidential information about clinical trials to investors. The story won the Scripps Howard National Journalism Award and several other national prizes. Luke holds a bachelor’s degree in journalism from the University of Wisconsin-Madison, and during the 2005-2006 academic year, he was a Knight Science Journalism Fellow at MIT.