Patent ID: 8287903

Claim:
A methylphenidate aqueous extended release oral suspension consisting of a combination of (a) a sustained release, cured, water-permeable, water-insoluble, non-ionic, polymeric diffusion barrier coated methylphenidate-ion exchange resin complexâ€”matrix, wherein the cured diffusion barrier coating comprises about 70 to about 90% polyvinylacetate, about 2.5 to about 15% of a plasticizer, and a stabilizer, (b) an immediate release methylphenidate component, (c) at least 50% by weight water based on the total weight of the liquid component of the suspension, and (d) pharmaceutically acceptable excipients, wherein said suspension has a pH of about 3.5 to about 5, and said suspension providing a therapeutically effective plasma profile of d-methylphenidate for about 12 hours and a single mean plasma concentration peak for d-methylphenidate.