Hey Suzanne!
There are some presentations on Estybon scheduled for this weekend's American Society of Hematology conference.
One presentation seems to link them all up into a summary, based on research done at St. Vincent's, Mt. Sinai, Stanford, and the NIH.
You can find the abstract here:
http://ash.confex.com/ash/2010/webprogram/Paper27358.html
Out of 48 patients, 13% had what the researchers term a "bone marrow complete response" (blasts go down 50% and stayed below 5% for at least four weeks) and another 27% saw their blasts decreased by half within 4 to 8 weeks. That 40% of patients lived significantly longer than the folks who didn't have such a dramatic response in their marrow.
Median survival among the 27% was 68 weeks. Five of the six who had complete response were still alive at the time the report was prepared.
The ASH abstracts include a couple of reports from the participating research centers:
http://ash.confex.com/ash/2010/webprogram/Paper34755.html
http://ash.confex.com/ash/2010/webpr...aper29141.html
One of these is at Stanford and the other at Mt. Sinai in NYC. Each appears to have treated ten patients and seen a response in five (50% response rate). That includes a couple of folks whose marrow returned completely to normal, as well as other folks who just saw improvements in blood counts.
The patients enrolled in these studies are older (median age 75 in one study and 80 in another), have more aggressive MDS, and have either failed to respond to or relapsed from treatment with Vidaza or Dacogen. In other words, these trials involve some tough cases, and that may lower the response rate to the drug.
A 50% response rate is about what you can expect with Vidaza, so it's nothing to sneeze at.
I gather that the way the drug works is to actually kill cancer cells (the abnormal MDS stem cells in this case), while not killing normal cells. The papers don't report many nasty side effects, though both mention a case of painful or difficult urination, both mention fatigue, one mentions nosebleed, and the other mentions anorexia.
Part of the goal of these trials was to figure out the dosing, so it looks like they tried a variety of schedules and it's not clear whether they've nailed down the best option. It's an IV drug and they were giving it to patients anywhere from 2 to 6 days a week, in some cases every week and in some cases every other week or even monthly.
The Leukemia and Lymphoma Society is helping underwrite research on the drug, so they evidently think it has some promise.
Hope that helps. Good luck to you and your Mom.
Greg