the reason there is a standard disclaimer is that the brain is too complex and no one can draw a straight, defensible line. But, relapse rate and new lesions seem to go hand in hand. That Tysabri patients saw 66% reduction in relapse rate v placebo (double the efficacy of the next best treatment - beta inteferons) is a good thing. That new lesions were reduced to virtually nil at the same time is amazing. Now we wait for 2 year data and EDSS scores.
The one year data that they have taken that 66% rate from is already suspect!
I did see the table link on the site which is a brief description of the trial data. I forwarded this to a friend of mine who has done a lot of research in MS and knows how to read these studies. Here are the comments that I got back...............
First of all the patients who were in Study 1 had a disease duration of 5 years versus the patients in Study 2 had a disease duration of 7 years and consequently the percentage of relapse change is significantly different between the two Studies. Furthermore, the patients in Study 1 which Biogen has been boasting that it showed a 66% decrease in relapse rate, most likely had a very low score on the EDSS because "approximately 94% had never been treated with these agents (interferons or copaxone)" but of course they don't bother to tell us what the median EDSS score was in this group. They only tell us that patients were enrolled that had an EDSS score between 0 and 5.0. Most likely the majority of these patients were closer to 0 given that 94% had never received any treatment. (My comment: I believe that Serono alluded to this lack of information in their recent press release on Tysabri.)
Next if you look at the tables in Figure 1 you will see that under MRI Endpoints it says that the median number of new or newly enlarging T2 lesions was 0.0 for the Tysabri group in Study 1 meaning that no new lesions were formed. Well since no new lesions were formed then that means that 60% of patients put in the Tysabri group never had any lesions to start with because it states that 60% of patients in the Tysabri group in Study 1 had no lesions.
Now more tell-tale is the Gd-enhancing lesions (active lesions) because the median in both the Tysabri group and the placebo group in Study 1 were 0.0, meaning no change from before they entered the study. This shows that 96% of the Tysabri group in Study 1 had no active lesions, but the placebo group had only 68% with no active lesions prior to the study. The Tysabri group had only 3% with 1 active lesion prior to the study, yet the placebo group had 13% with 1 active lesion prior to the study. The Tysabri group had only 1% with 2 or more active lesions prior to the study and the placebo group had 19% with 2 or more active lesions before the start of the study.
Study 2 is just more of the same.
So do you see how the study was manipulated to show benefit according to their measurements of effect. Of course I wish people would pay more attention to the real issue here as they boldly state "The exact relationship between MRI findings and the clinical status of patients is unknown. Changes in lesion area often do not correlate with changes in disability progression." So what is the point in using this criteria to determine if a drug is going to have any effect on a MS patients life?!!
I don't pretend to understand all the very complex data of a clinical trial but instead rely on people who do. I also received comment back from a member of the MS Consortium Group who specialize in MS treatment and research.....the individual told me that she and other members of this group are not very comfortable with the Tysabri data from Biogen.
Maybe the two year data from these trials will answer a number of quesitons that have gone unanswered so far. Maybe my and other people's major concerns about this drug will be laid to rest but until then and until a lot of people start to use Tysabri outside the clinical trial setting, I will be extremely cautious about Tysabri. I simply don't have a great deal of trust in pharmaceutical companies these days after what we have seen what happened with Merck(Vioxx) and Warner Lampbert. (Neurontin)