Dr. Barai,
>>I would NOT like to advise anyone, what stock to buy or not to buy. Each person should make their own decision. I would like to confine myself to science part of a product, and when appropriate, my interpretation of facts.<<
My sincerest apologies if you felt that I was implying that you were promoting or dispromoting a stock. I was merely agreeing with some of your points and disagreeing with others; a discourse, if you will. Of course, none of us would be here on SI if we weren't also interested in the financial consequences of the technology, and I know that any comments you would offer in that vein would also be appropriate.
I appreciated your response, and hope that you don't mind if I continue our discussion by responding to your points.
>>(1) I read with interest the claim that Biopure bovine Hb will be stable at room temp. I do have problem digesting that. I would like to know more about the validity of that claim and scientific data to back the claim. Recombinant Hb solution produced by Somatogen will be stable in refrigerated state for one YEAR. This is possible because, 6 weeks life of stored blood is due to metabloic reactions in RBCs, involving various enzymes. Since Hb solution will not have such metabolic enzymes, stability should be enhanced. They stated that they are working on lyophilized version for stability at room temp.<<
I did a quick search for data substantiating this claim, and have located at least one reference to this. Hughes (of Pharmacia Upjohn) in discussing the pharmacokinetics of the Biopure candidate states that it is stable at room temperature for greater than a year, and requires no reconsitution (so must not be lyophilized) to administer [Hughes, GS, et al. Critical Care Medicine, 24(5):756-64, 1996]. I must agree with you though that much of the shelf-life limitation of whole blood is due to the loss of certain enzymic functions in RBCs. My understanding, however, is that the mechanism of degradation in stroma-free Hb is an oxidation of the Hb to metHb; a reduction in temperature serves to reduce the rate of this reaction.
>>(2) I still believe that once genetically engineered product is available, very few people would want animal/bovine products. Even products which have been in use for years, get jettisioned quickly. It happened to Insulin, growth factor, Hepatitis vaccine. It is not only a question of blood borne infection, but idea of prefering synthetic or genetically engineered product over animal/bovine product.<<
I won't disagree with your analogy, IF the recombinant product is EQUIVALENT to or BETTER than the natural product, AND LESS EXPENSIVE. With insulin, the recombinant product is all of these. The concept of drawing and processing animal blood into an oxygen therapeutic IMO, however, is less like the production of porcine insulin than it is like the production of proteins in transgenic animals' milk (currently under intensive development).
>>(3) I must respectfully disagree with your contention that bovine products will not face supply constraint. How can one get millions of grams of Hb from birds? Which type and how many millions of birds can yeild such an industrial quantity of Hb?<<
I assume that you mean cattle? Biopure's product is made from polymerized BOVINE hemoglobin, a raw material which is readily available at any packing plant (though I'm sure Biopure isn't just mopping the stuff up off of the floor).
>>The time to demonstrate to FDA "safe and effective" for Human use is very demanding and lengthy, for everyone. Biopure is just starting to take the initial steps. If it is hard and cumbersome to conduct trials of Human or Genetically engineered product, bovine product will have even tougher time. First, they will have to prove that Human beings can tolerate the product without developing allergic reactions/ antibodies. Even if everything went picture perfect, it will be 5-7 years before the product can come to market.<<
I must admit I'm confused by your statement. The press release said that they are in or preparing to enter "advanced clinical trials," which I read as PIII or at least PIIb. I think that they have published on at least some PII work already, which means the FDA has already gotten a look at safety and initial efficacy data. IMO the type of financing that got done would not have happened unless the FDA had given the green light for further trials.
>>The fact that someone got financing is different and in no way implies that their product will work scientifically. All companies working on Hb substitutes had venture capital funding and financing. NO One has commercial product yet. How many Silicon valley companies and how many biotech companies have gone caput, after venture capital funding. REALITY IS THAT MOST BIG MONEY PEOPLE DO NOT HAVE DEEP SCIENTIFIC BACKGROUND TO UNDERSTAND THE VERY COMPLICATED SCIENCE INVOLVED AND THE NATURE OF THE PRODUCTS. In 1995, everyone thought that there was no end to demand for technology products, billions of Dollars were poured like crazy into tech stocks. Are we little more sober today?<<
Can't disagree with you on any of these points. My sole point initially was that it might be dangerous for us, whether our investments are in NFLD, Baxter, SMTG, ALLP or SYBD, to discount Biopure. As you said so well above, the BIG MONEY in them can't be counted on as an indication either.
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