Abstract: The invention relates to the complexation of RNA with optionally modified polyethylenimines for extracellular and intracellularin vitro and in vivo stabiliztion thereof and for cellular introduction of the complexed RNA in cells. The invention also relates to chemically modified or non-modified, natural or synthetic ribozymes complexes and polyethylenimine (PEI) having any chain length, molar mass and degree of branching, which is chemically modified or non-chemically modified. The invention further relates to the production of complexes and to the use thereof in the protection of RNA against enzymatic and non-enzymatic degradation and their reception in vitro or in vivo in cells. The biological activity of the ribozymes remains intact.

Abstract: Increased expression of a secreted FGF-binding protein (FGF-BP) occurs in certain autoimmune and malignant disease conditions. It is found, for example, that tumor secretions of FGF-BP results in mobilization and activation of locally-stored FGFs that can serve as an angiogenic switch molecule. Furthermore, it has been found that in an animal model of multiple sclerosis (MS), the exacerbation of the disease is accompanied by increased FGF-BP. Using ribozymes, it is possible to cause cleavage of the FGF-BP mRNA. Hence, administration of ribozymes which cleave the FGF-BP mRNA in sufficient amounts to inhibit disease processes triggered by FGF-BP is appropriate.