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Biotech / Medical : Zonagen (zona) - good buy? -- Ignore unavailable to you. Want to Upgrade?

To: Dauntless who wrote (2064)	1/27/1998 10:41:00 AM
From: Dr. Voodoo	Respond to of 7041

If you go back and check some of my old posts, I qualified my statement about Asensio's homework. As a scientist, whenever I see someone quoting a 1975 paper I would automatically assume that the method used to measure in 1997 may or may not be different. Also there is an apples to oranges effect. That is, unless I was in the same lab, (especially with 1975 data) using the same equipment, I (personal opinion)would usually run the control experiment, which if you'll notice from the patent application Zonagen apparently did. The question currently in my mind, and I will hope to get this info after some reading is, does this data make sense. Imhof's group seems convinced based on the physiological effects that phentolamine rapidly produces it's effects and is quickly eliminated(3hours). Now if you recall less than 5 ng/ml is what they found as a therapeutic concentration. Question then becomes(Even Bill will appreciate this one), if you have significantly changed the bioavailabity of phentolamine, have you changed the likelyhood of someone getting a toxic dose? More reading. I'm not near done yet. Got lots of red herrings to chase.

To: Dauntless who wrote (2064)	1/27/1998 3:59:00 PM
From: Dr. Voodoo	Read Replies (2) \| Respond to of 7041

Dauntless, Went and read J chromatography articles did not copy, no quarters, very grumpy thing :( What my interpretation of what I read is: The phentolamine levels they measured in blood were low. I forgot the time points. They did not mention numbers. Go forth and check the patent application. In this chrom. paper they administered a 20 mg dose. Look at Zonagen's own numbers. They indicate that the mean was right around 5 ngs. Also look at the standard deviation. What this says to me irrespective of time points is that you cannot make a reliable determination of phentolamine levels in blood by looking at that paper based on a 20 mg dose. As a result, Zonagen went to higher doses. Among interesting points I got out of the paper were half life of 19 minutes. Also a bunch of cool words like rapidly metabolized, and conjugated and unconjugated. I am not an analytical chemist, but I have a pretty good understanding what they did to develop their assay. Among the things I still can't quite glean is whether or not they actually measured the metabolite in urine or just said it was difficult. I would be careful in interpreting the urine data, that one is a little tricky. There was one other reference to an HPLC determination of phentolamine levels down to like 15ng/ml. More on this later, if it pans out. Regarding Asensio, and lawsuits and other stuff. I do not want to be involved. I don't care about any of this vindictive schmeg. I would advise you to talk to someone who can get a real expert determination of what is going on and don't rely on my chemical or scientific judgement and opinions. (I am not and do not want to be an expert, I just pretend to be one on the internet!) My interpretations of the data are just that, my interpretations, which I have shared with you and others. Still fetching papers, they're getting popular around here!