Claims for Patent: 5,807,825

Summary for Patent: 5,807,825

Title:	Platelet aggregation inhibitors
Abstract:	An assay for screening snake venom for the presence or absence of platelet aggregation inhibitors (PAIs) based on specific receptor binding is described. Using this assay, the identification and characterization of PAIs in a wide range of snake venom samples was accomplished. The isolated and purified PAI from several of these active snake venoms is described and characterized. In addition, PAIs lacking the Arg-Gly-Asp (RGD) adhesion sequence but containing K*-(G/Sar)-D wherein K* is a modified lysyl residue of the formula R.sup.1.sub.2 N(CH.sub.2).sub.4 CHNHCO-- wherein each R1 is independently H, alkyl(1-6C) or at most one R1 is R2 --C═NR3 wherein R2 is H, alkyl(1-6C), phenyl or benzyl, or is NR4 2 in which each R4 is independently H or alkyl(1-6C) and R is H, alkyl(1-6C), phenyl or benzyl, or R2 --C═NR3 is a radical selected from the group consisting of: ##STR1## where m is an integer of 2-3, and each R5 is independently H or alkyl(1-6C); and wherein one or two (CH2) may be replaced by O or S provided said O or S is not adjacent to another heteroatom are prepared and shown to specifically inhibit the binding of fibrinogen or von Willebrand Factor to GP IIb-IIIa.
Inventor(s):	Robert M. Scarborough, David Lawrence Wolf, Israel F. Charo
Assignee:	COR Therapeutics Inc, Millennium Pharmaceuticals Inc
Application Number:	US08/482,278
Patent Claims: