I'm hoping that someone can help clear this up for me, perhaps George, if you don't mind...
What exactly is the success rate of the HSCT cure? Am I right in saying that it's 100% in rrms and 80% in s/ppms It seems like that's what George is saying on his blog?
I'm confused! Is the disease not halted in 100% of cases, and if not, why not?
Here are the basic probability statistics that is supported by the finite study population data. . . .
Ealy RRMS-treated patients
Essentially 100% stopping of the disease process & progression.
81% of the same group experiences "significant" improvement (>1.0 point EDSS) reduction of existing symptomatic EDSS. Many HSCT-treated patients in this group report their symptoms completey dissappearing, 100%.
During the RRMS phase of the disease I would expect very good beneficial results following HSCT regardless of the EDSS symptomatic disability at the time of treatment.
Late SPMS (non ambulatory) treated patients
78% stopping of disease progression
EDSS improvement not quantified
Curative efficacy is not population-quantified in other patient EDSS stratum. So for the SPMS patients with an ambulatory status, the cure rate (stopping of diasease progression) is not well established, but certainly I would expect it to be greater than 78%
Just my own personal expeience data point (that does not necessarily translate to any other specific individual) that appears to be consistent and fairly representative of other (ambulatory) SPMS patients so far. . . . . I was RRMS for 11 years and then went SPMS for 4 years (EDSS 3.5) before my HSCT procedure. As of today (18 months post-transplantation) my disease is 100% stopped and my pre-existing symptomatic deficit (as measured by EDSS) has improved (reversed) 40% (currently at EDSS 2.0). So clearly it is possible that SPMS cases (especially those that are ambulatory) can experience good benefit from HSCT.
Late PPMS (non ambulatory) treated patients
66% stopping of disease progression
EDSS improvement likely poor, if at all
So for the PPMS patients with an ambulatory status, the cure rate (stopping of diasease progression) is not well established, but certainly I would expect it to be greater than 66%.
Also, for ambulatory PPMS cases, EDSS improvement is possible, but not gauranteed. This is a very un-studied and unknown area. I would expect this number of people in this poulation to show improvement somewhere in the chasm-like range of 1% - 65%. Perhaps someday as more ambulatory PPMS patients are treated then this can be better quantified. For now, the treated population is so small its impossible to predict with any confidence.
But no matter what, HSCT has a far better chance of having a positve beneficial effect for MS patients compared to any (every) other therapy anywhere in the world. So far, no other curative therapy can even come close in accomplishing what HSCT has already (scientifically and repeatably) demonstrated.
Regarding all of the above information, you can read the overview here. . . . .
http://themscure.blogspot.com/2010/06/s ... rence.html
And as to your last question. . . . "I'm confused! Is the disease not halted in 100% of cases, and if not, why not?"
This is an excellent question! It's true that less than 100% of MS patients will experience a halting of MS disease activity via HSCT (although the vast majority will). Like everything in nature, there are no certainties, just probabilities. The reason it does not work in 100% of all MS cases is still unknown. As the research and clinical treatment continues, at some point in the future I imagine that this issue will be better understood.