Souped-Up Herceptin Aims to Validate ImmunoGen’s Long-Sought Dream Cancer Drug

is to attach antibody to the toxin in a way that makes the whole drug stable in the bloodstream, so that the cell-killing payload is released in the tumor where it belongs, Junius says. Genentech already had an antibody that it knew hit a proper target on cells for about one-fourth of breast cancer patients. What it needed was a method to link that antibody to a toxin from ImmunoGen to make it more potent.

This may sound straightforward, but the field has been plagued with failures. The first drug to work like this, Wyeth’s gemtuzumab ozogamicin (Mylotarg), has been a commercial flop since it was approved in May 2000. One key reason: The drug didn’t have a stable enough linker between the antibody and the toxin, which meant that the toxin broke off early and started floating around the bloodstream, causing side effects, before it could get to the tumors. (ImmunoGen isn’t the only company with an idea on how to solve this problem. Bothell, WA-based Seattle Genetics (NASDAQ: [[ticker:SGEN]]) has been soaring this year after it reported outstanding results of an empowered antibody drug for Hodgkin’s disease at a medical meeting in December.)

If ImmunoGen has really solved this problem, it stands to reap big rewards. Antibody drugs as a class generated $18 billion in sales in 2008, Junius says. Worldwide sales of Herceptin alone exceeded $4.3 billion last year, and ImmunoGen stands to collect a “mid-single digit” royalty on worldwide sales of the newer version. That means if the more potent Herceptin can reach that same level of sales, and ImmunoGen actually gets a 5 percent royalty, it would collect $215 million a year without having to spend a penny on its own sales force.

Junius is clearly excited to have such meaty data from Genentech to tell investors about, but he’s also quick to point out ImmunoGen isn’t putting all its eggs in that one basket. The company has eight drugs in clinical trials, five of which are being pushed ahead by partners, while it retains full ownership of three others, Junius says. The current pipeline is built on hard knocks of the past, in which ImmunoGen learned that certain tumors respond differently to drugs that combine antibodies with toxins. (For example, for cell biology nerds out there, it apparently makes a difference whether the antibody itself gets chopped up once inside a tumor, or whether the linker gets sliced up to release the toxin, Junius says.)

Like with every biotech company today, I had to ask Junius if he has enough cash to soldier on through this downturn. ImmunoGen has about a year’s worth of cash on hand, so it still needs to watch its expenses carefully, especially in a stock market where it’s not easy to hit up investors for another round of financing, Junius says.

Junius, 56, has spent his career on the financial side of the business, and was promoted from chief financial officer to CEO in January to replace Mitchel Sayare. Maybe because ImmunoGen has been humbled by dashed hopes of the past, Junius said he wanted to steer clear of too much bravado.

For example, at the end of our conversation, when I asked him if he has a vision of building up a sales and marketing team and becoming a fully-integrated company, he said he has no intention of building up that capability now. The company needs to watch its spending, he says. ImmunoGen has suffered in the past from what he called “self-inflicted wounds” in which it struggled to get people to enroll in studies fast enough, which is important in order to get a clear answer on how to best spend company resources, he says.

“I’m probably the wrong kind of guy to be in this industry, but I’m actually risk-averse,” Junius says. “We really should walk before we try to run. Right now, we’re somewhere between crawling and walking.”

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.