]-3-(2-fluoro-5-trifluoromethylphenyl)urea, N-methyl-4-{4-[3-(2-fluoro-4-trifluoromethylphenyl)ureido]phenylsulfanyl}pyridine-2-carboxamide, and pharmaceutically usable derivatives, salts, solvates and stereoisomers thereof, including mixtures thereof in all ratios.