Probably I am not qualified to comments about Zomaril ongoing PIII trials, still have several points on which I do do not agree (or have different view) with your general statements. Not that I am expert or anything close but have learned from others who may be qualified viewers for this field.
So, here are my (their) points:
1. Schizophrenia is not crowded with current available therapy. Two drugs are leader (olanzepine or Zyprexa and risperidone or Risperdal, while Novartis clozapine or Clozaril is losing market shares), and will continue to expand market shares in expense of the older drugs. PFE and ABT candidates failed while Zeneca drug has serious side effects to grab higher market shares (over $4B today). So, another *me-too* drug with comparable therapeutic benefit (close to Zyprexa and/or Risperdal) with Novartis marketing muscles will sell well or even be full home-run.
2. There are *me-too* and *ME-TOO* drugs. BIG difference. Early during clinical development stage LLY Zyprexa was *me-too* drug (olanzepine is structuraly sister to Novartis first atypical anti-psyhotic drug clozapine), but when drug didn't show side-effects associated with Clozaril it become leading drug in schizophrenia market. Also, Risperidone is structurally similar to haloperidol, still without extrapyramidal side effects.
3. Very similar structure for two drugs or binding to some class receptors (postulated therapeutic action. however with some difference) not necessary means that drug therapeutic benefit (when CNS disorder is on plate) will be similar. Sometime small structural difference, or even one atom (*S* instead *C* when olanzepine is compared to clozapine) may make big difference or whole new game. So, no way to predict what will be Zomaril results in real world (PIII clinical trials and post-marketing studies). Zomaril or iloperidone is structurally similar to risperidone.
4. In cells receptors model Zomaril show some difference in binding strength for several receptors (D2, -3, -4, 5HT2A, -2C, -6, ...) compared to other atypical anti-psychotic drugs, as well in animal and human studies pharmacology was found to be favorable. This doesn't guaranty anything, but do show promise that drug may bring some improvement (in side effects profile) compared to today leaders on market. The problem is not enough data to project drug efficiency. So, if Novartis have preliminary data from first PIII trials (drug versus haloperidol versus placebo) and if it show positive results, the Zomaril is suddenly emerging from latency as good candidate.
I am optimistic that Zomaril will show comparable efficiency with fewer side effects, which will make drug more compelling for growing anty-psyhotic market (with some off label potential). More than enough for tiny TTP to emerge as interesting investment opportunity.
Two more things about TTP:
1. Pivanex and ongoing PII NCCLC trial. It appears that drug have passed first part of this trials (minimum responded pts in first group, for expansion to full enrollment). I mentioned this early and am probably repeating myself. Pivanex is pivaloyl-oxymethyl derivative of n-butyric acid (well known cells differentiation agents and apoptosis inducer, but highly toxic). The some structural derivatization are in GILD HIV NRTI candidates: PEMA and PMPA (actually two very potent viral RTI with significantly, over 100 times, improved pharmacokinetic by this derivatization or pro-drug formulation). So, this derivatization/pro-drug formulationof the n-butyric acid have some chance to work in specific cancer types and this may be TTP second chance.
2. Regards the vaccines and Spheramine I will become believers when I see partners.
Miljenko
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