Biotech Values

[DewDiligence]

Re: GTCB and antithrombin availability

>>OK, what's "fractionation bias"? Trying to understand exactly why this product is not available…<<

Fractionation bias is the technique used by plasma-protein suppliers to calibrate which plasma proteins they produce in what quantities. The process of extracting and separating proteins from plasma destroys some of the proteins. In general, the greater the volume of one protein that is preserved in the final output, the less the volume that is preserved of other proteins from the same plasma source.

Talecris Biotherapeutics, which recently acquired Bayer’s U.S, plasma business (#msg-5925270), does not produce enough antithrombin to satisfy the clinical needs of the HD population in the U.S. And that brings us to your next question…

>>…and what do the patients do without it?<<

Under normal circumstances, individuals with HD can get by with an oral anticoagulant such as Warfarin (a.k.a. Coumadin). If they are undergoing surgery or childbirth, however, these individuals have a major dilemma. There are some clumsy ad-hoc workarounds with various drug cocktails, but these are not really satisfactory and certainly not a substitute for the antithrombin that the patients lack.

>>Also, is the plasma ($75m sales) that is used in Europe/Japan simply not available in USA?<<

That’s right – it is not available. Since the mad-cow outbreak in Britain a few years ago, the FDA has prohibited plasma-based proteins to be brought to the U.S. from other countries.