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Biotech / Medical : PTN - Palatin Technologies Inc. -- Ignore unavailable to you. Want to Upgrade?

To: sjemmeri who wrote (138)	11/6/2006 9:19:31 PM
From: rareearth42	Respond to of 142

Interesting phase 2b data today. Efficacy was about as expected and there was a nice dose response; more data than what're reported in the PR are available in a javascript presentation linked on the Palatin website front page that I can't cut-and-paste; palatin.com The big surprise was the frequency of discontinuation due to adverse effects and I think this explains the less-than-enthusiastic response of the market today. The hypertensive response in some patients (they didn't say what percentage) was also new to me, and that has possibly caused an over-reaction by the market, since most investors think of hypertension in the context of a chronic drug therapy, which is clearly bad, however for an occasional drug therapy such as bremelanotide it should be acceptable, no different than the hypertension that accompanies exercise, or sex for that matter. Here are the data for study 16: Dose.......Efficacy P value.......% discontinuation Placebo...............N/A.........................4 5 mg.....................0.2........................12 7.5 mg..................0.03.......................23 10 mg...................0.001......................27 12.5 mg...............0.004......................34 15 mg................<0.001......................53 The efficacy of the 5 mg dose was borderline in aggregate, although I suspect there were some who responsed nicely and others who didn't. We don't know if the receptor down-regulates with agonist treatment (it might), so we don't know if it would be possible for patients to take a sniff of 5 mg and if that's inadequate, repeat it. This is mixed news. The good news is that there's really obvious evidence of a pharmacologic effect; there's an excellent dose response for efficacy and for adverse effects, and most patients will be able to tolerate a 5 mg - 10 mg dose with good clinical results. The bad news is that the frequency of adverse effects is higher than we had been told previously and hypertension is a new and probably mechanism-based adverse effect, but it should be acceptable in a drug for intermittent use. Consider that PDE5 inhibitors cause hypotension, possibly severe if used with nitrates, and they're acceptable. The nausea and vomiting is probably also mechanism-based, remember MRK was studying MC4 receptor agonists for the weight loss application; I'm waiting eagerly to hear about weight loss in the study 16 groups, as if we see anything at all given the intermittent therapy, it will be big news. I'd also like to know if the nausea abated with repeated use or if it were present repeatedly. Overall it seems very likely there's a path forward to phase 3 and ultimately approval. The safety issue will be a real concern at the FDA and I suspect the open-label safety study to be conducted in phase 3 will have to be larger than previously planned as there are now more questions to answer. I'm going to hold onto PTN at least through phase 3. RE42