Oral Dosage Form Comprising Rosiglitazone

A process for preparing an oral dosage form which dosage form comprises a first composition and a second composition, each composition comprising a drug, where the drug is 5-[4-[2-(N-methyl-N-(2 pyridyl)amino)ethoxy]benzyl]thiazolidine-2,4-dione, or a pharmaceutically acceptable salt or hydrate thereof, and a pharmaceutically acceptable carrier therefor, wherein the first and second compositions are arranged to release the drug at differing release rates on administration such that the rate of release of the drug from the dosage form is substantially independent of pH;

• which process comprises the steps of sequentially or simultaneously:
• (i) formulating the drug into the first composition;
• and
• (ii) formulating the drug into the second composition;
• and the steps of sequentially or simultaneously:
• (i) forming the first composition into a first layer;
• and
• (ii) forming the second composition into a second layer;
• and
• (iii) combining the layers into a multilayer dosage form,
• whereby the first and second layers are formulated to release drug at differing release rates on administration such that the rate of release of the drug from the dosage form is substantially independent of pH.