By Matthew Willett
Abgenix Inc. and ImmunoGen Inc. are collaborating in an anticancer deal worth more than $20 million that links Abgenix's fully human XenoMouse antibodies with ImmunoGen's maytansinoid Tumor-Activated Prodrug technology.
Abgenix will pay a $5 million technology access fee for the ability to use ImmunoGen's TAP technology, and the Fremont, Calif.-based company also will purchase $15 million of ImmunoGen stock at $19 per share. ImmunoGen, of Cambridge, Mass., also will receive undisclosed milestone payments, and royalties on net sales of any resulting products.
Abgenix's stock (NASDAQ:ABGX) closed Wednesday at $69.375, down $3.313. ImmunoGen shares (NASDAQ:IMGN) closed at $17.563, down 31.25 cents.
Kurt Leutzinger, Abgenix's chief financial officer, said the collaborative products could have broad applications in anticancer therapeutics. Putting the technologies together creates a potent weapon against cancer, he said.
"We're the aiming mechanism and they're the bullet," Leutzinger said. "The fastest way to develop a cancer drug is to determine how to tell the difference between cancer cells and normal cells and design an antibody that attaches to the target that's much more commonly expressed on a cancer cell than a normal cell, and use that to deliver a toxin."
He said the deal fits Abgenix's business plan of partnering out compounds after Phase II testing.
"The rationale for this is that we expect to be seeing from our collaborations many cancer targets, and this is a way to exploit those targets to develop therapeutics which we can partner with large pharmaceutical companies after Phase II," Leutzinger said.
Abgenix's XenoMouse technology enables the company to rapidly produce therapeutics using transgenic mice. The maytansinoid TAP from ImmunoGen has origins in a family of potent chemotherapeutic agents the company said is a thousand-fold more cytotoxic than existing chemotherapeutics.
Using XenoMouse technology to create fully human antibodies has benefit for cancer applications, Leutzinger said, because of the fully human antibody's durability.
"The mouse components can reduce the half-life of the antibody in the patient, and the antibody doesn't have enough time to work," Leutzinger said. "It may not be able to deal with the cancer. The fully human antibody has a half-life of about three weeks, according to our own clinical trials, so the fully human antibody allows the drug to work on the cancer for a longer period of time before the body eliminates it."
Leutzinger said there's practically no limit to the targets the collaboration could spawn.
"It's a large number of targets, and by that we mean we don't see any practical limitations for us," he said. "There are more than we'll need to deal with all the cancer targets we expect to get in from our partnerships, both current and future." n