San Diego’s Polaris Moves to Late-Stage Test of Drug for Liver Cancer and Other “Arginine-Dependant” Tumors

Bor-Wen Wu says he had the North Star in mind in 2006 when he founded San Diego’s Polaris Group, a small holding company with a promising lead drug candidate for treating liver cancer, malignant melanoma, and other related cancers. As an explorer in science, Wu says, “I need a North Star to tell me where to go.”

Yet the path Wu has followed has been anything but a sure and constant course. In his quest to develop the drug ADI-PEG 20, Wu has formed eight companies since 2002 that are affiliated with Polaris; raised more than $60 million from individual investors in Taiwan; and battled to retain control of ADI-PEG after paying millions to acquire a predecessor company, Phoenix Pharmacologics of Lexington, KY.

Despite a sometimes-circuitous path, though, Wu has kept the Polaris Group focused on a distant goal. The FDA recently approved the company’s plans for a late-stage clinical trial of ADI-PEG 20, an enzyme also known as pegylated arginine deiminase. ADI-PEG 20 is incredibly effective in breaking down arginine, an amino acid that is critical to the growth of hepatocellular carcinoma—the primary type of liver cancer.

Among cancer drugs in Phase 3 trials, Wu boasts, “We’re not the first in class. We’re the only one in the class. There’s nothing in the rear-view mirror.”

A study published last year in the British Journal of Cancer estimates there are 500,000 new cases of hepatocellular cancer diagnosed worldwide annually, with a five-year survival rate of less than 10 percent in the United States and Europe. Polaris, which contends the liver cancer is far more prevalent in Asia, estimates that worldwide deaths from hepatocellular carcinoma is closer to 700,000 people a year, with more than 330,000, or nearly half, in China.

ADI-PEG 20 represents an especially hot area of cancer research, which has focused on finding ways to starve tumors by depriving them of key nutrients. In the case of liver cancer, Wu says a key genetic mutation that triggers hepatocellular carcinoma coincides with the specific gene that makes arginine in normal cells. The company says the correlation is more than 70 percent in the patients studied so far. As a result, most liver tumor cells are unable to manufacture their own arginine and depend on some other source of

Author: Bruce V. Bigelow

In Memoriam: Our dear friend Bruce V. Bigelow passed away on June 29, 2018. He was the editor of Xconomy San Diego from 2008 to 2018. Read more about his life and work here. Bruce Bigelow joined Xconomy from the business desk of the San Diego Union-Tribune. He was a member of the team of reporters who were awarded the 2006 Pulitzer Prize in National Reporting for uncovering bribes paid to San Diego Republican Rep. Randy “Duke” Cunningham in exchange for special legislation earmarks. He also shared a 2006 award for enterprise reporting from the Society of Business Editors and Writers for “In Harm’s Way,” an article about the extraordinary casualty rate among employees working in Iraq for San Diego’s Titan Corp. He has written extensively about the 2002 corporate accounting scandal at software goliath Peregrine Systems. He also was a Gerald Loeb Award finalist and National Headline Award winner for “The Toymaker,” a 14-part chronicle of a San Diego start-up company. He takes special satisfaction, though, that the series was included in the library for nonfiction narrative journalism at the Nieman Foundation for Journalism at Harvard University. Bigelow graduated from U.C. Berkeley in 1977 with a degree in English Literature and from the Columbia University Graduate School of Journalism in 1979. Before joining the Union-Tribune in 1990, he worked for the Associated Press in Los Angeles and The Kansas City Times.