StarLac® is a new co-processed excipient, based on 85% lactose and 15% starch, commercially available for direct compression. Purpose of the study is to compare the powder and tablet characteristics of this new compound vs. the physical blend based on lactose and starch. The most important characteristics for direct compression like compaction behavior, stability of the compound, flowability, Mg-stearate sensitivity and disintegration as well as dissolution are highlighted.

The compound as well as the formulations with an active showed better flowability and lower tendency of de-mixing.

Most important, there is practically no influence of the Mg-stearate concentration and over a wide range of the tablet hardness on the disintegration or dissolution, which is faster compared to the physical mixture.