When developing solid-dispersion formulations of poorly soluble APIs, one must do the following: compare the API functional
groups with the polymer functional groups, compare the API solubility parameters with polymer solubility parameters, and analyze
the expected permeability of the API to determine which polymers to evaluate for solid-dispersion technology. The most soluble
or most stable formulation should not necessarily always be chosen for further process development because many factors (e.g.,
API permeability window, polymer supply, polymer toxicology, physical product characteristics, and processing yields) can
have a substantial impact on the final product. These issues must be considered before moving forward with product development.
Timothy Bee is a senior director and Mohammed Rahman* is a project leader/solid-dispersion scientist, both at International Specialty Products (ISP), tel. 410.910.7414, firstname.lastname@example.org
*To whom all correspondence should be addressed.
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