The present invention is related to a nucleic acid molecule comprising a double-stranded structure, wherein the double-stranded structure is formed by a first strand and a second strand, wherein the first strand consist of the following nucleotide sequence 5′ acGaGcUgGaCcAcUgGuCdTsdT 3′, and the second strand consists of the following nucleotide sequence 5′ GAcCaGuGgUcCaGcUcGudTsdT 3′, wherein a minor nucleotide indicates that the nucleotide is 2′-F modified and an underlined nucleotide indicates that the nucleotide is 2′-0-methyl modified and wherein dTsdT indicates that at the 3′ end a dinucleotide is attached consisting of two dT nucleotides, wherein said two dTs are covalently linked through a phosphorothioate bond.