title: Toxicology studies with recombinant staphylokinase and with SY 161-P5, a polyethylene glycol-derivatized cysteine-substitution mutant.
abstract: SY 161-P5, a polyethylene glycol derivatized (PEGylated) mutant of the recombinant Staphylokinase (rSak) variant SakSTAR, exhibiting reduced antigenicity is in clinical development for treatment of acute myocardial infarction as a single bolus injection. A series of safety studies were performed in vivo as a routine toxicology program with SY 161-P5 (PEG-rSakSTAR) and with the recombinant Staphylokinase variant Sak42D (rSak42D). For both compounds, intravenous single bolus injections of up to 100-fold therapeutic equivalent, as well as repeated injections during 7 to 28 days revealed no significant pathological findings in mice, rats or hamsters. However, New Zealand white rabbits developed clinically silent, multifocal myocarditis following single or repeat doses of SY 161-P5 or of Sak42D. These findings were dose-independent and reversible. A similar species-specific cardiotoxic effect has previously been described for other proteolytic proteins, including the approved drugs Streptokinase and Acetylated Plasminogen Streptokinase Complex (APSAC). The large experience with these drugs, as well as the clinical data accumulated both with PEGylated and non-PEGylated rSak variants to date, do not indicate cardiotoxic hazards associated with the use of these drugs in humans.
authors.affiliation: Center for Transgene Technology and Gene Therapy, Flanders Interuniversity Institute for Biotechnology, KU Leuven, Belgium.
authors.forename: L
authors.initials: L
authors.lastname: Moons
authors.forename: I
authors.initials: I
authors.lastname: Vanlinthout
authors.forename: I
authors.initials: I
authors.lastname: Roelants
authors.forename: R
authors.initials: R
authors.lastname: Moreadith
authors.forename: D
authors.initials: D
authors.lastname: Collen
authors.forename: H J
authors.initials: HJ
authors.lastname: Rapold
mesh_terms: D000818:Animals; D003545:Cysteine / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D005260:Female; D005343:Fibrinolytic Agents / Q000633:toxicity*; D006321:Heart / Q000187:drug effects*; D007275:Injections, Intravenous; D008297:Male; D008666:Metalloendopeptidases / Q000633:toxicity*; D051379:Mice; D009203:Myocardial Infarction / Q000139:chemically induced / Q000473:pathology; D009205:Myocarditis / Q000139:chemically induced* / Q000473:pathology; D011092:Polyethylene Glycols / Q000737:chemistry; D011817:Rabbits; D051381:Rats; D011994:Recombinant Proteins / Q000633:toxicity; D013045:Species Specificity; D018675:Toxicity Tests
chemical_list: D005343:Fibrinolytic Agents; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D008666:Metalloendopeptidases; C439267:SY 161-P5; C022653:auR protein, Staphylococcus aureus; D003545:Cysteine