Eben Tessari

Wyeth and Elan Take Hits on Bad Trials

Bozak,
Thanks for reading. There is absolutely no connection between any adverse events seen with Tysabri vs Bapineuzumab. Two completely different mechanisms.

Tysabri got in trouble because it does it's job too well. It suppresses the immune system by inhibiting a molecule (a4B1 integrin) used by immune cells to get into the brain. Exactly what you want if you have MS. Unfortunately, it did this job so well that an opportunistic virus, PML for short, showed up in a few patients (though none since the initial scare).

So far, the most important adverse event for bapineuzumab has been vasogenic edema, or fluid buildup in the brain. This is really really not good, especially because the amount of fluid was dose dependently related to the amount of drug given.

Anyway, two completely different problems. Hope that helps. I added some links if you want to know more.

en.wikipedia.org/wiki/...
en.wikipedia.org/wiki/...
en.wikipedia.org/wiki/...