The Value of Powder Testing In Developing Continuous Tableting Processes

A collaborative research project between Freeman Technology and GEA Pharma Systems is providing new insight to support the development of continuous tablet manufacturing processes, a long term goal for the pharmaceutical industry. Both companies are investing significant resource in the project and it is expected to deliver further substantive results over the next quarter.

Within the pharmaceutical industry the replacement of batch tablet production units with continuous manufacturing suites has the potential to significantly improve efficiency and reduce costs. Freeman Technology, a global leader in powder testing instrumentation, and GEA, a specialist provider of pharmaceutical processing equipment, are combining their expertise to advance understanding in this area. A primary focus is to identify metrics that provide a sound basis for the effective control of continuous manufacturing processes.

The production of tablets often involves wet granulation of a fine powder blend, followed by compression of the resulting dried, milled and lubricated granules. In this research GEA’s ConsiGma™ 1 continuous granulation unit is being used to produce granules for tableting, which are then characterised using Freeman Technology’s FT4 Powder Rheometer®. Direct correlations are observed between the flow properties of the granules and critical quality attributes of finished tablets, such as hardness. These correlations highlight the potential of dynamic powder testing as an at-line Process Analytical Technology (PAT) for continuous tablet manufacture.

Building on early success in applying powder flowability data to scope the design space for the ConsiGma™ 1, current goals are to establish links between wet granule flow properties and observed tablet weight variability at production speeds. Often sub-optimal granules are associated with low manufacturing speeds and/or high weight variability in the finished product. A partial aim of the current work is to show how dynamic powder characterisation can be used to optimise continuous granulation so as to avoid these problems.