DM-1 thoughts

[Rich66]

I wonder if financial agreements/funding are the only reason Immunogen is combining DM1 solely with Traz(Herceptin). If the other T, Tykerb, has a second receptor (her1) to bring the DM1 to..why not? Sounds like double the displeasure for the cancer cell.
I also wonder whether hormone (or other) receptor treatments could deliver the DM1. Is DM1's mechanism only effective on Her2+ cells?

[chrisy]

I'm not a molecular biologist, don't even play one on tv. I think there are many reasons why it is "trastuzumab-DM1" instead of a myriad of combinations.

First and foremost, it took them quite some time to be able to effectively attach the DM1 to the Herceptin. Don't forget the full name of the drug is T-MCC-DM1 with the MCC being a separate piece linking the DM1 to the herceptin, then releasing it into the target cell. One of the big holdups on this drug, as I understand it, was getting the linker to work - because the DM1 is so toxic you really don't want it released into the general bloodstream. I suspect that future applications would include trying to use that MCC link to attach to more of both type of molecules (the "smart" targeting agent and the "bomb" toxin). It's probably not so simple as just hooking it onto the next targeting agent (tykerb) that comes along.

DM1 is a powerful toxin, so it would probably work well on many types of cancer, the problem is it is so toxic it needs the "smart" part or it would be too toxic to use. So you'd have to find a target, then have a drug (like herceptin) that would deliver to the target. So it's more that it can only be USED on Her2+ cancer because that's the only one that they can target in this way.

Also, they do not yet really have "proof" that it works. Only now are they beginning phase III trials where they can actually compare it to other therapies. The present focus would be on proving that the Herceptin DM1 works and getting it through the approval system.

But I'd have to agree with what I think is your underlying point: I sure wish they would hurry up!

[Rich66]

" It's probably not so simple as just hooking it onto the next targeting agent (tykerb) that comes along."

Why not, dangit? (arms folded)
How about sending the DM1 in via nano-thingies?

[chrisy]

Hey Rich, I'm with you - let's just stomp our feet until they get it done!

[Rich66]

"One of the biggest problems with developing antibodies for cancer is that most of them have no therapeutic effect by themselves, even if they target and bind cancer cells specifically. As a result, for every Herceptin out there, there are dozens, if not hundreds of antibodies who can bind and recognize specific antigens on cancer cells, but have no therapeutic use. Attaching drugs to those antibodies may turn many of them into very potent agents, regardless of their inactivity as naked antibodies. All of the sudden, those “useless” antibodies turn into an infinite pool of potential drugs, so there is no need to develop new antibodies. That is why, in our opinion, technologies such as Immunogen’s do not only advance the field of cancer antibodies toward safer and more effective treatments, but actually represent a true revolution, as it shortens time-to-market of potential drugs. Since there are so many well studied antibodies that have already been developed and characterized, the resources and time required for bringing such immunoconjugates to the clinic become dramatically lower."

http://www.hammerstockblog.com/immun...tin-dm1-t-dm1/

[runtolive]

http://www.ksdk.com/news/local/story...174101&catid=3