Disclosed are novel novel polymorphic solvated and desolvated forms of the sodium salt of 4-tert-butyl-N-[chloro-2-(1-oxy-pyridine-4-carbonyl-phenyl]-benzenesulfonamide. One embodiment of the present invention is directed to a crystalline sodium salt of 4-tert-butyl-N-[4-chloro-2-(1-oxy-pyridine-4-carbonyl)-phenyl]benzenesulfonamide (hereinafter “Compound A-1,4-dioxane/water solvate”), wherein the crystalline form is characterized by an X-ray powder diffraction pattern comprising diffraction angles (° 28), when measured using Cu Ku radiation, at about 4.0, 8.1, 10.1, 14.2, 16.2, 18.6, 20.3, 24.7, 25.0, and 26.5.
