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

To: Mark the K who wrote (4983)	7/21/1998 10:21:00 PM
From: Cacaito	Respond to of 7041

Mark the k, to chek other products rejected by the FDA check: CORR, rejected for some of the indications (angina) but not for the main one (actual myocardial infarct). Check the thread. They have the statitistical different, but needed literally 10,000 patients to prove a minimal different of 1.5%, so if the sample is large enough your get your number, but not the FDA approval. ERGO, non approval letter for Ergotamine for diabetes (they want it for dieting too, bad timing around the Redux debacle), stock from $18 to $3, but the FDA final decision is pending (it seems nobody wants to wait for it). DEPO, good result but few patients, they did not got the famous statistical Chi Square less than 0.05, they are negotiating another trial or something else with the FDA. Stock tanked. SCIO, recently halted by the Data Safety Monitoring Board, independent counselors of the FDA to decide about not good and/or actually harmful, but continues in Europe in different dosage infusion for stroke. Baxter, kills more patients with their drug substitute and DSMB halted the trial. LGND, Panretin European study halted for great results in Kaposi's. Actual good news. There you will see a nice report, with all the data, and nice numbers, of a novel anticancer drug, for comparison. AMLN, check their results, good for type I diabetes, marginal for type II and the stock tanked, their report is full with numbers and statistics, very comprehensive. IPIC, even more traumatic, they have good numbers, good statistics, in two studies for citicoline in strokes, then they got bad results in MRI imaging (some says complex and good), the FDA informed then that the submision is a sure rejection and sent back even before the NDA, to try for another long, large study, Stock tanked again (they tanked with Redux removal from the market). TXB, their drug got a non approval letter, it could be they have some chance, but the stock tanked. Even worse (or good for others )a similar compound from Merck got approved very recently, so either theirs does not work, or the trials were poorly designed, no data is out to my knowledge ( some call it Zonagen's sister company, the same neighborhood The Woodlands). Most of the information one can find in the threads, others in the prnewswire.com archives, or in the companies web sites. Some have too many patients, with marginal differences(CORR), others few patients with marginal statistics (DEPO), others harmful, others marginal efficacy and bad timing (ERGO at the time of Redux), others were sent back to the drawing board (IPIC), a lucky one LGND got an early positive halt (stock is not moving anyway). Conclusion, it is very tough to read the mind of the FDA and their advisory boards (many time in conflicting recommendations, but the final decision is the FDA), and even sometimes the DSMB gets in the way much before (halting studies for being too good, or too harmful).

To: Mark the K who wrote (4983)	7/21/1998 11:16:00 PM
From: Cacaito	Read Replies (1) \| Respond to of 7041

Mark The K Part two, Zonagen's numbers vs Viagra: 1. Forget Vasomax 80 mg results, it is not the intended dose and they have no practical difference from the 40 mg. 2.The 80 mg dose was to prove the lack of serious side effects and if I remember well the FDA ask for it, not originally in the plans, they got what they want it, more stuffy noses but not much more hypotension (for the study population, preselected as per Asensio). Population was preselected, if poor cardiovascular status, patients were excluded from the studies. Well, this is the ethical thing to do, one does not want to kill patients advertently (Asensio is wrong when he claims it is a shortfall, maybe a longfall?). 3. Two sets of results, The "overall" group including all the patients at 40 mg of Phentolamine 51% erections (75% of the attempts achieving penetration) vs 38% with placebo. The penetrations in "75% of the attempts" makes the interpretation tougher, to get the 100% success will one decrease 25% the efficacy for both the drug and placebo? ( 75% of 51% is = 38.25% for the drug, and ( 75% of 38% = 28.5% for placebo) or (phentolamine 38.25% vs placebo 28.5%) this way is just plain terrible, but IT IS NOT A VALID WAY to decide, because we do not have the whole protocol in the hands. 4.Consider placebo response as 1 time (or 100%), and the drug improvement will be 51%/38% = 1.3 times or only 0.3 times more successful than placebo (or 30% better than placebo). 5. For Viagra: overall " 69% of all attempts successful vs 22% placebo" this is 69%/22% = 3.14 this is 2.14 times better than placebo (or 214% better than placebo). 6. But, the Zonagen's researchers (I. Goldstein) are smart dealing with the public and the FDA, and this is the hidden card, either by design or by a reexamination of the data (I suspect the latter), they found a way, they found "groups" of patients that did better than the "overall" this were the mild group "or the less severe" and in this group: phentolamine 40% vs placebo 15%. Here they could trick even Asensio (I am sure he has no respond for this one). this is an eye popping wow 40%/15% = 2.67 times better or 267% above placebo, this is in the Viagra range of effectiveness ( for the "less severe")category. I will refer you to the ABTI disaster with their infectious prevention drug Betaglucan, they are trying to present to the FDA the post study re-examined data as an NDA, the market cleverly responded tanking the stock from $12 to $2. The FDA just does not tolerate "re-examined" data, they know it is easily manipulated, even with good intentions, because the data is already unblinded (not double blind anymore, once the study is open). The FDA wants the predicted results from the original plans, otherwise is rejection or back to the drawing board, not the post study "re-examinations". That is good to present academic papers in ones' resume, but not for the FDA. Zonagen's chance is that they originally planned this "less severe" ED population. They could ask the FDA for approval in that population and maybe they have a chance. If it is re-examine data then back to the drawing board. Anybody out there has the original protocols? Caveat # 1: a year ago I was a long for a short period. Since then no position in the stock. Too much uncertainty, too much risk to both sides longs and shorts. I will go in later after the FDA decision. Caveat # 2: the comparison phentolamine-viagra has a problem, the end points are not exactly known for phentolamine, they are in the New England Journal of Medicine for Viagra.