**4.3 Filler in dry granulation**

Roller compaction is a dry process involving compaction of materials that are then milled to generate a granulation. This granulation is then lubricated and compressed on a tablet machine. This process can be used for moisture-sensitive active pharmaceutical ingredients. The use of Avicel PH grades in roller compaction includes improvement of compaction in the ribbon phase, enhancement of flow of the granules, and preserving of the content uniformity of the Þ nal granulation.
