Improved RIT?

Someone posted this article to the support group. It's actually almost two years old, but I think only recently became available to the public. It's called "Improved Therapy by Pretargeted Radioimmunotherapy of Non-Hodgkin Lymphoma with a New Recombinant, Trivalent, Anti-
CD20, Bispecific Antibody," and it was published in July 2008 in Cancer Research. The article describes an improved way of administering RIT (RadioImmunoTherapy). It's only been tried on mice in a lab, but it sounds very promising.

First, a reminder: RadioImmunoTherapy involves taking a monoclonal antibody (like my pal Rituxan), which finds and latches on to the protein CD20 on lymphoma cells, and adding to it a dose of raditation. So when the antibody attaches to the lymphoma cell, it is zapped with that radiation payload. RIT has been a very effective treatment for a lot of people.

Now, this article describes a change in the way the radiation is delivered. If I'm reading it correctly, instead of delivering the antibody with the radiation attached to it, the two are sent in separate parts. The antibody attaches to the lymphoma cells, and a day later, the raditon is delivered separately. The radioactive particles are constructed so they seek out the antibody and attach to them.

The radioactive particles are somehow able to (I'm not sure how) find their target quckly, do their job, and then leave the bloodstream quickly -- much more quickly than RIT currently is able to be cleared out. Less radiation in the bloodstream is a good thing. The quick clearing from the blood means that more radition is allowed to be given, increasing the chances that all of the lymphoma cells will get hit.

So it seems like this method means less toxicity with better results. That's the one-two punch we're all looking for with future treatments.

One downside is that this kind of method adds a step to an already complex process, and that complexity (it has to be done by a nuclear medicine specialist, not by a regular old oncologist) might deter some people.

On the other hand, lots of docs have already been put off by the complexity of administering RIT (among other reasons), but very positive results from clinical trials seem to be changing some minds. So maybe as this method moves through trials, the (we assume) excellent results will change more minds.