Disclosed is a modified release pharmaceutical formulation, comprising: N-(2-amino-4-(fluorobenzylamino)-phenyl) carbamic acid ethyl ester (retigabine), or a pharmaceutically acceptable salt, solvate or hydrate thereof； a drug delivery matrix comprising hydroxypropylmethylcellulose (HPMC), an anionic surfactant and an enteric polymer, said pharmaceutical formulation producing a sustained plasma concentration of said retigabine following administration to a subject for 4-20 hours longer than the time required for in vitro release of 80% of said retigabine. The pharmaceutical formulation is useful for treating a disorder characterized by nervous system hyperexcitability such as a seizure disorder.
