HarryZ wrote: Given that the Tysabri group was twice the size of the placebo group, the percentage of effect should have been greater than twice the placebo effect to demonstrate even a little more effect than the placebo. Thus the results point to the probability that if the placebo group had been as large as the Tysabri group, the placebo group would have had as good or better effect than the Tysabri group in improving physical disability.
I´m also not very good at statistics but that sounds strange to me..
Could you explain?
You don't expect me to try and figure that out, do you?
However, I did ask for clarification from my source and this is what I received...
.......The percentage tells you the amount of change seen, but the power tells you how dependable the results are and that they are not just by chance. You can increase the power of a study by increasing the size of the study. The percentage of change may stay the same with the larger study but given that there was only a difference of 11% with a Tysabri group twice as large as the placebo group, it is unlikely that they would have reached significance with a smaller Tysabri group. Remember the size of the groups is determined by the anticipated effect of the drug. The greater the effect of the drug the smaller the number of subjects you need....
What we have seen from Biogen here is some fancy statistical dredging in an attempt to promote the sale of Tysabri. This is what marketing departments of big pharma do....promote their drugs to increase sales and profit. This data was available two years ago from the Affirm trial yet Biogen is only now telling us about it??!! Like I said earlier, their anticipated sales are way below forecast and they need to stimulate more interest in the medication.
But please don't equate my suspicions about Biogen with the hope that any patient who decides to try Tysabri, gets some kind of benefit from it. Another reader has suggested that since I have never had MS myself, I don't appreciate what benefits Tysabri may give a person. My wife had MS for 36 years and prior to that my uncle had it for 25 years. I have seen what devastation this lousy disease can inflict. At the same time, I have followed the development and marketing of all the currently approved MS drugs (others as well) and have seen how the companies who make them can twist information to make it sound very good.
Unlike the CRAB drugs, Tysabri has basically been tested and used on patients who have mild cases of MS. It is far easier to get an IV once every 28 days than to inject one's self as often as the CRAB drugs require. That in itself brings a level of comfort to MS patients that never existed with the CRABs. The often nasty side effects of the CRABs are also not missed. Again, more cause for excitement and better feeling.
But don't get mislead by some of the Tysabri cheerleaders on the internet or by Biogen who likes to tell MS patients that this drug is the ANSWER to MS. It hasn't been around long enough and used by very large numbers of patients to determine how good or bad it may be. So far I have read that some patients do very well on it, others notice no change at all and some end up become sicker and have to stop using the drug. Sound familiar with MS medications? And again, the data that is used is from mild MS patients.
I really hope that in the long run, Tysabri provides a much better result to MS patients than the CRABs ever did because those drugs never did much for them. I also wish that the range of $3000-10,000 per Tysabri infusion was a lot lower. That kind of cost can bankrupt health care costs!