Roche-ImmunoGen to Start T-DM1 Trials - TheStreet

WALTHAM, Mass. (

TheStreet

) --

ImmunoGen

(IMGN) - Get Report

is expected to announce Monday a commitment by its partner

Roche

to begin new late-stage clinical trials of the experimental breast cancer drug T-DM1.

The overall goal of this new clinical trial program will be to determine whether T-DM1, which is still not approved for use, can one day replace Roche's Herceptin as the leading treatment for women with certain breast cancers.

Herceptin global sales totaled $3.8 billion in the first nine months of 2009 and $4.7 billion in sales in 2008, according to Roche.

The

Genentech

unit of Roche will start a phase III study of T-DM1 in first-line breast cancer in May 2010. Additionally, a clinical trial designed to evaluate T-DM1 in the post-surgical, or adjuvant, setting is also in the planning stages, Immunogen will announce.

T-DM1 is a second-generation version of Roche's Herceptin. It consists of Herceptin (also known as trastuzumab) linked to a tumor-killing chemotherapy payload developed by ImmunoGen.

Roche's new commitment to advance T-DM1 comes as the drug maker plans to meet with the U.S. Food and Drug Administration to discuss seeking approval for T-DM1 as a third-line treatment for breast cancer patients.

On Saturday, researchers presented new clinical data from a phase II study showing that T-DM1 shrank tumors in 33% of critically ill breast cancer patients. The 110 patients in this study were essentially out of medical options because their breast cancer was no longer responding to treatment with Herceptin or

GlaxoSmithKline's

(GSK) - Get Report

Tykerb.

Patients in the study also went an average of 7.3 months before their tumors began to grow again.

"These are breast cancer patients who do not have a lot options at this point. And what we see with T-DM1 is that it really offers benefit. I'm quite encouraged and I think this drug is significant for patients who really need help," said Dr. Ian Krop of the Boston's Dana Farber Cancer Institute Krop and the lead investigator of the T-DM1 study.

Based on these data, Krop said he'd like to see Roche seek regulatory approval soon.

"T-DM1 is a drug that I'd like to see made available to patients. I'm sure Genentech

Roche is strongly considering using this data for the basis of an accelerated approval filing," he said.

Krop presented his findings from the T-DM1 study at the San Antonio Breast Cancer Symposium. ImmunoGen first disclosed

partial results

from the study on Wednesday.

T-DM1, like Herceptin, is designed to be most effective in patients with excess levels of a protein known as Her-2 that causes breast tumors to grow more aggressively. Almost 40% of patients with confirmed Her-2 positive status in the study saw their breast cancer tumors shrink.

If Roche does seek FDA approval for T-DM1, the drug would be the first treatment approved as a third-line treatment for breast cancer. T-DM1 would also be the first approved drug for ImmunoGen, which is set to receive mid single-digit royalties on T-DM1 sales by Roche.

The T-DM1 data presented Saturday "are quite the validating statement for our technology," said ImmunoGen CEO Dan Janius. "A year from now, we could have T-DM1 on the market for an indication where there is no approved therapy today."

Roche is conducting already conducting a separate phase III study testing T-DM1 head-to-head against Glaxo's Tykerb in second-line breast cancer patients. A phase II study of T-DM1 compared to Herceptin in first-line breast cancer will have data ready for presentation at an upcoming medical meeting.

ImmunoGen shares closed Friday at $8.77.

Adam Feuerstein writes regularly for TheStreet.com. In keeping with TSC's editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet.com. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback;

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