Seagen Inc (SGEN)

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HUGE NEWS ARTICLE OUT ABOUT SGEN IN NYTIMES!!!


https://www.nytimes.com/2012/06/01/business/a-new-class-of-cancer-drugs-may-be-less-toxic.html


The New York Times
May 31, 2012
A New Class of Cancer Drugs May Be Less Toxic
By ANDREW POLLACK
Fern Saitowitz’s advanced breast cancer was controlled for about a year by the drug Herceptin and a toxic chemotherapy agent. But her hair fell out, her fingernails turned black and she was constantly fatigued.

She switched to an experimental treatment, which also consisted of Herceptin and a chemotherapy agent. Only this time, the two drugs were attached to each other, keeping the toxic agent inactive until the Herceptin carried it to the tumor. Side effects, other than temporary nausea and some muscle cramps, vanished.

“I’m able to live a normal life,” said Ms. Saitowitz, 47, a mother of two young children in Los Angeles. “I haven’t lost any of my hair.”

The experimental treatment, called T-DM1, is a harbinger of a new class of cancer drugs that may be more effective and less toxic than many existing treatments. By harnessing antibodies to deliver toxic payloads to cancer cells, while largely sparing healthy cells, the drugs are a step toward the “magic bullets” against cancer first envisioned by Paul Ehrlich, a German Nobel laureate, about 100 years ago.

“It’s almost like we’re masking the chemotherapy,” said Dr. Edith Perez, a breast cancer specialist at the Mayo Clinic in Jacksonville, Fla.

One such drug, Adcetris, developed by Seattle Genetics, was approved last August to treat Hodgkin’s lymphoma and another rare cancer. TDM-1, developed by Genentech, could reach the market next year. Data from a large clinical trial of T-DM1 is expected to attract attention at the annual meeting of the American Society of Clinical Oncology this weekend in Chicago.

Numerous other companies, from pharmaceutical giants to tiny start-ups, are pursuing the treatments, which are known variously as antibody-drug conjugates, armed antibodies or empowered antibodies. “I don’t think there is a major pharma or a midsized pharma with interest in cancer that doesn’t have a program or isn’t scrambling to put one together,” said Stephen Evans-Freke, a managing general partner at Celtic Therapeutics, an investment firm that recently committed $50 million to create a new company, ADC Therapeutics, to develop antibody-drug conjugates.

About 25 such drugs from a variety of companies are in clinical trials, according to Alain Beck, a French pharmaceutical researcher who closely tracks the field. Genentech alone has eight in clinical trials besides T-DM1, and another 17 in earlier stages of development.

Many of the drugs use technology from either Seattle Genetics, based in Bothell, Wash., or ImmunoGen of Waltham, Mass., which supplied the toxin and linker used in T-DM1....

Continued in Part 2

In one trial involving 137 women, including Ms. Saitowitz, T-DM1 proved both more effective and less toxic than a combination of Herceptin and the chemotherapy drug docetaxel as an initial treatment for metastatic breast cancer.

Those who received T-DM1 went a median of 14.2 months before their disease worsened, compared with 9.2 months for those getting the two-drug combination. Yet only 46 percent of the T-DM1 patients suffered a severe side effect, half the rate of the other group.

At the cancer conference, researchers will present results of a pivotal trial involving nearly 1,000 women. Though armed antibodies are easy to envision, it has taken more than three decades to make them practical, with many failures along the way.

With the first armed antibody to reach the market, Mylotarg, the toxin sometimes fell off the antibody prematurely, causing side effects. Approved in 2000 to treat acute myeloid leukemia, Mylotarg was removed from the market by its manufacturer, Pfizer, in 2010 after new studies showed it did not prolong lives and had safety problems.

Since then, two antibodies linked to radioactive isotopes have been approved to treat non-Hodgkin’s lymphoma — Bexxar from GlaxoSmithKline and Zevalin from Spectrum Pharmaceuticals. These drugs, while effective, are more cumbersome to use than antibodies linked to chemical toxins.

Researchers first tried to use existing chemotherapy drugs as the payloads, but they were simply not toxic enough. That is because less of a drug gets to the tumor when carried on an antibody than when the drug floods the body by itself.

Seattle Genetics and ImmunoGen use toxins that are hundreds of times as potent as typical chemotherapy agents. They are too toxic to be given by themselves.

The linkers have proved even tricker to develop since they must keep the toxin attached to the antibody while in the bloodstream, but then release the toxin inside the cancer cell.

Dr. John Lambert, executive vice president for research and development at ImmunoGen, will be in the audience at the cancer conference as the fruits of 30 years of work are presented.

“To get to this point is an indescribable feeling, actually,” he said.