The rilutek question is more complicated than the "three months" calculations. I'm not even sure where that number comes from. Initial studies showed rilutek to be neuroprotective. The two "double-blind" studies done thereafter, which formed the basis of FDA approval, actually showed a benefit at ,6, 9 and 12 months but not 18 months. These have become controversial results to some PALS who claim that the numbers were "fudged" because aparently in one of the studies, different measures were used to calculate the final results than had originally been proposed.
Since then multiple reviews of the drug have been done. An open label study done with Mexican patients found a statistically significant slowing of disease progression:
Results
One-year treatment ended January 1998 for the 50 patients initially enrolled, of which 31 (62%) completed the study. Of those did not complete treatment protocol, 14 (28%) were because of non-compliance with study visits our voluntary drop-out, mainly in the first two month of treatment with riluzole; 4 patients (8%) died of respiratory failure (none of them presented treatment related side-effects), within a mean of 5 month after riluzole was started; one patient (2%) has to continue drug therapy because of skin rash which disappeared after stopping riluzole.
Thirty-one patients (11 women, 35% and 20 men, 65%), with a men age of 47.67 (SD 10.35) years (49.16 years for women and 44.63 years for men) completed the one-year treatment. Mean clinical evolution of ALS was 25.83 (SD 13.43) months (29.66 months in women and 23.73 months in men). None of the patients had a greater then two-fold increase in aminotransferase . Mean values for alanine aminotransferase and aspartate aminotransferase were 27.78 U/L at study entry, and 27.58 U/L and 26.76 U/L at the end of one-year therapy, respectively. Complete blood counts were not significantly different before and after treatment.
Full Article->
http://www.medicosecuador.com/revecuatneurol/vol8_n3_1999/open_label_study_of_riluzole.htm
The "Cochrane" review of existing studies concluded rilutek conferred a two-month survival extension, but also cautioned these results were skewed by the fact that one study included multiple older, fast-progressing patients:
(broken link removed)
Perhaps most intriguing were reports from three separate patient databases presented at the 2001 International Symposium on ALS describing long range
experience with riluzole. All three reports suggest a trend of increasing survival with riluzole over time. It was concluded that "more studies that are double blind and controlled are needed to confirm these database observations. The trend appears to indicate that longer periods of time than those used in the riluzole clinical trials may be needed to see the long-term survival advantage of the drug."
http://www.als.ca/_news/64.aspx
Interestingly, I find no evidence that any such "studies" were ever done to confirm the database observations. It seems to me, then, that rilutek may be far more effective than the original studies indicated; my own nueurologist told me that current thinking among his colleagues is that the drug is more likely to be beneficial when given to patients in earlier stages of the disease and that it is probably much better than most doctors originally thought. Now, that may be self-delusional puffery to make the docs think they are doing something they really aren't. But it is interesting nonetheless.
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