Patent ID: 8580301

Claim:
A method for the manufacture of a pharmaceutical composition comprising two distinct components, the first component containing an initial dosage of a psychostimulant and the second component containing a second dosage of said psychostimulant, wherein said psychostimulant is methylphenidate, and wherein the release of said second dosage is modified, characterized in that the release of said second dosage is modified by a single layer coating, wherein the single layer coating is an enteric coating comprising (co-)polymers of (meth)acrylic acid and/or (meth)acrylate containing carboxyl groups, thereby causing a sustained release of said second dosage of the psychostimulant in vivo, and wherein the in vivo release of the pharmaceutical composition is characterized by one single main plasma peak, comprising the steps of: a) manufacturing the first component by: providing spheres, preparing a liquid containing a psychostimulant, coating the spheres with said liquid, and drying the coated spheres; b) manufacturing the second component by: providing spheres manufactured in accordance with step a), preparing a liquid suitable for providing an enteric coating on said spheres, the liquid containing (co-)polymers of (meth)acrylic acid and/or (meth)acrylate having carboxyl groups and an alkaline agent selected from the group consisting of NaOH and KOH, wherein the alkaline agent is added to the liquid in an amount sufficient to achieve a neutralization of 3-8% of said carboxyl groups, coating the spheres with said liquid, and drying the coated spheres, thereby forming an enteric coating layer comprising channels which allow for diffusion of the psychostimulant through the enteric coating layer at a pH below 5.5.