Models have been developed for predicting relative powder-flow performance using PSD data. The PLS model, which used D10,
D50, D90, and D[4,3] as input parameters, is suitable for predicting the FFC value for APIs and excipients and may also be
appropriate for predicting PSD influences on other materials (e.g., active blends and active granulations). This empirical
tool leverages a material and resource-sparing approach to the powder-flow performance characterization. In addition, the
tool can be particularly useful during prototype drug-product design, especially with regard to risk assessments when little
is known about the flow performance of a new API or excipient.
The authors would like to thank Bruno Hancock for reviewing this work and providing technical guidance.
Matthew P. Mullarney* and Norma Leyva are senior scientists at Pfizer, Inc., Eastern Point Rd., Groton, CT 06340, tel. 860.715.4139, firstname.lastname@example.org
*To whom all correspondence should be addressed.
Submitted: June 16, 2008. Accepted: July 8, 2008.
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