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Biotech / Medical : XOMA. Bull or Bear? -- Ignore unavailable to you. Want to Upgrade?

To: aknahow who wrote (9020)	3/9/1999 12:16:00 PM
From: Chris Boylan	Read Replies (2) \| Respond to of 17367

> from george wohanka > Since the trial was not stopped earlier or now because of > futility, we know Neuprex is producing a favorable result. While I largely agree with everything you said on this one point I would differ somewhat. You can not assume that Neuprex is producing a favorable result because the study is continuing. It might be, for example, they have accumulated 34 deaths to date. 17 in the control group, 15 in the Neuprex group. And two months ago it might have been 13 in the control group and 15 in the Neuprex group. Neither snap shot would be meaningful if statistically they need 45 overall deaths, given the size of the trial, to have a p value acceptable to the FDA AC. [These numbers are completely bogus obviously and are for illustration purposes only.] > Wonder if the DSMB was even asked if the target can now be > revealed? I would respect a logical reason for not revealing > the target. This is an area where I think there has been a little spin control (and rightly so) on the part of XOMA. The important underlying point here is that XOMA designed the phase III trial, not the DSMB; the DSMB is a creation of XOMA designed to oversee the trial within the guidelines established by XOMA as an impartial entity not subject to any outside interests. I'd bet money (sort of already did) that XOMA explicitly decided up front not to release any results on an interim. What if they LOOKED bad? They wouldn't be statistically valid and the stock would still tank. It would complicate their raising cash periodically. As an aside, one thing I realized last night was that they MIGHT be getting patients enrolled that are too healthy and instead of the supposedly "normal" 20% death rate in the control group they reported in the phase I/II maybe they are seeing (say) 8%. This would be bullish as it would just mean they completely screwed up when they estimated the required trial size but that the results might still somewhat mirror the phase I/II results. I've been worried for the last 6 months that the study problem was that there was statistically insignificant spread in the death rates between the two groups.

To: aknahow who wrote (9020)	3/9/1999 2:43:00 PM
From: Edscharp	Read Replies (2) \| Respond to of 17367

George, Two inquires, if you don't mind. #1) I haven't had any exposure to statistics since my college days. I've probably forgotten more than I ever learned anyway. Suppose the DSMB called you and said, "Yeah, our target is 50 deaths". How does that number help your statistical analysis? Unless you had all the other data this number wouldn't seem to be very helpful. #2) I've only been to this thread a short time. I've noticed that previous to today the mood on this thread has been rather somber and pessimistic. Lo & behold, the DSMB report comes in and today some of our thread participants have become decidedly combative and testy. Is this thread normally like this? May I reasonably conclude that a little bit of knowledge is a dangerous thing? Might this be the answer as to why DSMB releases as little data as possible?