<<I was wondering if you cared to offer more specific examples (i.e. which drug?)>>
Mind if I jump in here? I've been looking at NZYM recently so checked the thread.
Of the 27 NCEs introduced last year (1998), two had amino-acid building blocks, both synthetic. Interestingly, both are anti-thrombotics (clopidogrel {Plavix, Iscover} from Sanofi and tirofiban {Aggrastat} from Merck). All but one of these (formavirsen {Vitravene} from ISIS) are small molecules. Source: "Annual Reports in Medicinal Chemistry, Vol. 34".
Frankly, I don't see that ratio changing all that much going forward. Of compounds that I know of that are in development at various companies, less than 10% would use an amino acid building block. Just about the first thing any medicinal chemist does when he finds an amino acid moiety in a lead compound is to change it to something else. Just look at the HIV protease inhibitors: by and large, their PK and PD parameters are terrible. If people weren't dying every day from this disease, most of those compounds would not have made it to the clinic.
Although Synthetech makes some nice research tools, I don't see them hitting a lot of home runs in the manufacturing arena. But then, they really only need a few base hits to make it, so it's possible. |
