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Biotech / Medical : VVUS: VIVUS INC. (NASDAQ) -- Ignore unavailable to you. Want to Upgrade?

To: BigKNY3 who wrote (4093)	12/30/1997 2:23:00 PM
From: Tunica Albuginea	Respond to of 23519

Big KNY3, MUSE I believe is very good! To you 37 % success may seem low, but these WERE ALL HARD CORE ED patients. The KEY point here is that the success rate for Viagra in these patients is likely to be even less. Maybe less than 10%. Most Viagra studies were done on younger people and they stress that these were patients of " no known organic cause ". Viagra is " an erection enhancer".You have to be able to have some erection on your own to get any effect. Also these patients may have been sicker than the ones in the MUSE study. This study was independent. The study says that if these people tried it at home the sucess rate might have been higher, ( the initial MUSE study was done at home. Don't forget the Viagra study patients were " visually stimulated " for 1-2 hours before having an erection!! What was the nature of visual stimulation? Strip-tease? Other? Belly dancer? The Viagra study doesn't tell us. The MUSE patients in the NEJM on the other hand were all in " a stable monogamous" situation at home. They were tested with their wife. She might not have resembled ANY of the " Visual Stimulation samples " tested with the Viagra patients!!. You need to be very carefull in interpreting studies. I will post the recent phosphodiesterase destruction/ retinal degeneration study/blindness which I think has some serious implications for Viagra. Just today the Wall St Jour, mentioned how SELDANE one of the MOST popular antihistamines for the last 10 years HAS BEEN TAKEN O F F the market because it caused too many deaths. THOSE are ther problems of drugs with heavy systmic exposure. TA

To: BigKNY3 who wrote (4093)	12/30/1997 2:36:00 PM
From: Tunica Albuginea	Respond to of 23519

Retinal Degeneration in Mice Lacking the,gamma Subunit of the Rod CGMP Phosphodiesterase Stephen H. Tsang, Peter Gouras, Clyde K. Yamashita, Hild Kjeldbye, John Fisher,* Debora B. Farber, Stephen P. Goff-, The retinal cyclic guanosine 3',5'-monophosphate (CGMP) phosphodiesterase (PDE) is a key regulator of phototransduction in the vertebrate visual system. PDE consists of a catalytic core of a and b subunits associated with two inhibitory g ( gamma ) subunits. A gene-targeting approach was used to disrupt the mouse PDE-g gene. This mutation resulted in a rapid retinal degeneration resembling human retinitis pigmentosa. In homozygous mutant mice, reduced rather than increased PDE activity was apparent; the PDEap dimer was formed but lacked hydrolytic activity. Thus, the inhibitory -g subunit appears to be necessary for integrity of the photoreceptors and expression of PDE activity in vivo ooooooo Our results indicate that an interaction between the gamma subunit and PDE ab is essential for the proper activation of PDE and that all three subunits may be essential for assembly of a stable, active holo enzyme. The genetic loss of PDEGamma is manifested as an increase in cGMP content in the developing mutant retinas. The hi cGMP concentrations may keep cGMP-gated cationic channels open ____________________________________________________________________ continuously and lead to an excessive energy load on the rod ____________________________________________________________ photoreceptors resulting in degeneration. _________________________________________ ********************************* S.H. Tsang, J Fisher, S. P. Goff, Howard Hughes Med co nstitute, Department of Biochemistry and Molecular Biophysics, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA. P Gouras and H. Kjeldtye, Edward Harkness Eye Institute, Department of Ophthalmology, Columbia University, College of Physicians and Surgeons, New York, NY 10O32, USA. C.K. Yamash la and C. S. Farber, Jules Stein Eye Institute. Molecular Biology Institute and Department of Ophthalmology UCLA School of Medicine, Los Angeles, CA 90095, USA. 'Present address: Regeneron Pharmaceutcas, Tarry lesson, NY 10591. USA, SCIENCE - VOL. 272 - 17 MAY 1996 ********************************* COMMENT (mine ): Viagra studies have shown that patients get " blue halos " around their visual field.It is easy to link that to Sildenafil/Viagra's inhibition of PDE ( phosphodiesterase), which in essence is not different than what the above study did, ie, genetically destruy it. The study clearly shows that the retina NEEDS PDE around to inhibit/keep the level of cyclicGMP low because if cGMP rise then the retina is continuosly stimulated which lesds to retinal degeneration. But that is ectly what Viagra does!!: keep cGMP high in the corpora cavernosa to cause penile vasodilatation!! Well it appears to me that whereas penoile tumescence is good, " retinal tumescence!! " leads to premature blindness degeneratioin. TA

To: BigKNY3 who wrote (4093)	12/30/1997 2:51:00 PM
From: Tunica Albuginea	Respond to of 23519

Big KNY3, besides retinal degeneration, here is a recent example of other systemic/previously approved drug side effects: ************************************* The Wall Street Journal Interactive Edition -- December 30, 1997 Hoechst Allergy Drug Seldane To Be Pulled Off U.S. Shelves Dow Jones Newswires WASHINGTON -- Hoechst Marion Roussel said it will pull its allergy drug Seldane off the U.S. market Feb. 1. Introduced in 1985, Seldane was the first prescription antihistamine that didn't cause drowsiness. It once held 80% of the market for allergy drugs. But this past January, the Food and Drug Administration began proceedings to force Seldane off the market because of the risk of cardiac complications when used in combination with a number of other medications. Hoechst Marion, a unit of Hoechst AG of Germany, had balked at the FDA moves, but in September agreed to add language to its Seldane product labels warning against its use with certain other drugs. The announcement of Seldane's withdrawal from the market came as Hoechst Marion said Allegra-D, an addition to its Allegra line of nonsedating allergy drugs, received FDA marketing clearance. Allegra-D is a reformulation that adds the decongestant pseudoephedrine hydrochloride. A Hoechst Marion spokeswoman said the company wanted permission to also sell a decongestant version of Allegra before it withdrew Seldane. Seldane will continue to be sold overseas for now because Allegra hasn't been widely introduced abroad, the spokeswoman said. Hoechst's decision didn't affect the generic version of Seldane, known chemically as terfenadine. The FDA also plans to ban generic terfenadine, and maker Ivax Corp. is fighting the attempt. FDA pulmonary-drug chief John Jenkins said that unless Ivax changes its position, the government will proceed toward a formal ban of all terfenadine products. Ivax couldn't be reached for comment. Dr. Jenkins couldn't say how much longer it will take the FDA to finalize a ban. Unless a drug is declared an imminent danger, which Seldane and its generic weren't, the agency must go through court-like proceedings to order a ban. In the meantime, Dr. Jenkins's advice for terfenadine users is to choose Allegra. "We see no reason that someone should be taking terfenadine," he said. In 1992, doctors found that Seldane was dangerous for people with liver disease and that those who took the antihistamine in addition to certain other medicines could suffer potentially fatal heart rhythm problems. The FDA warned consumers and doctors never to prescribe the risky drugs together, but it didn't immediately move to ban Seldane because it did relieve allergies. Then in July 1996, the FDA approved Allegra, a safer version of Seldane that can be used by people with liver disease and taken with other medications. ********************************************************** TA

To: BigKNY3 who wrote (4093)	12/30/1997 7:36:00 PM
From: Cacaito	Respond to of 23519

Imagine the combination Muse/prazosin. Are those studies ongoing or still projects? Out of margin, on the edge: cacaito

To: BigKNY3 who wrote (4093)	1/1/1998 10:30:00 AM
From: MissLil	Respond to of 23519

I agree this is not a good study. Problems: 1. "Control" is based on self-reported results with injections. 2. Control injection is not specified. 3. Criteria for entry into study are not defined. 4. No adequate protocol for injection specified. 5. No "blinding." An adequate study would have a "double-blind, double-dummy" design with all patients receiving and injection and intrapenile deposition of either placebo or active drug. 6. Study compares "apples and oranges." i.e. comparison of triple drug therapy injected with single drug therapy intra-urethral. This is just what occurs to me off the top of my head. If someone tried to send this into the FDA the reviewers would die laughing.