Claims for Patent: 6,423,342

Summary for Patent: 6,423,342

Title:	Process for the preparation of a solid pharmaceutical dosage form
Abstract:	A process for the preparation of a solid pharmaceutical dosage form comprising a carrier and, as active ingredient, a compound which exists, in solution, in an equilibrium between a free acid or free base form and a salt form, and for which there is a difference in volatility between the free acid or free base form and the salt form. The process includes the steps of solidifying a mixture of the compound and carrier in a solvent, and subsequently removing the solvent from the solidified mixture. A pH modifier is added to the mixture prior to solidification to shift the equilibrium to favor the less volatile form of the active ingredient.
Inventor(s):	Jordan; Andrew William (Swindon, GB), Saunders; Joy Elaine (Faringdon, GB), Kearney; Patrick (Swindon, GB)
Assignee:	R. P. Scherer Corporation (St. Petersburg, FL)
Application Number:	09/305,080
Patent Claims:	1. A process for the preparation of a solid, fast dispersing pharmaceutical dosage form comprising a carrier and, as active ingredient, selegiline or an acid-addition salt thereof, said process includes the steps of solidifying a mixture of selegiline or an acid-addition salt thereof and carrier in a solvent and subsequently removing the solvent from the solidified mixture, characterized in that a pH modifier which produces a less volatile form of the active ingredient is added to the mixture prior to solidification to shift the equilibrium to favor the less volatile form of the active ingredient. 2. A process according to claim 1, wherein the pH modifier lowers the pH of the mixture. 3. A process according to claim 1, wherein the pH modifier is selected from a group of compounds including citric acid, tartaric acid, phosphoric acid, hydrochloric acid, and maleic acid. 4. A process according to claim 1, wherein the pH modifier comprises 0.25 to 0.75% by weight of the mixture. 5. A process for the preparation of a solid pharmaceutical dosage form comprising a carrier and, as active ingredient, a compound which exit, in solution, in an equilibrium between a free acid or free base form and a salt form and for which there is a difference in volatility between the free acid or free base form and the salt form, which process includes the steps of solidifying a mixture of the compound and carrier in a solvent and subsequently removing the solvent from the solidified mixture, characterized in that the solidified mixture is maintained within a temperature range of -15 to -25.degree. C. for a period of time of at least 18 hours prior to removal of the solvent. 6. A process according to claim 5, wherein the specified time period is at least 24 hours. 7. A solid pharmaceutical dosage form prepared by a process according to claim 1. 8. A process according to claim 1 wherein said pH modifier is selected from a group of compounds including sodium hydroxide, potassium hydroxide and carbonates and bicarbonates of sodium and potassium, propanolamine, ethanolamine, methylamine, dimethylformamide, dimethylacetamide, diethanolamine, diisopropylamine and triethanolamine.