Improvements of the oral bioavailability of lipophilic drugs can be obtained using lipidic formulations such as the
self-emulsifying drug delivery systems. The high shear wet granulation (HSWG), using microemulsions as
binder, is a viable process to produce self-emulsifying granules. However only few information are present in
the literature on the effect of process variables on the properties of the granules obtained with these binders.
Consequently, this article compares the effects of some relevant experimental variables (impeller speed and
massing time) on thefinal technological and pharmaceutical properties of the granules produced using simple
water, or alternatively, a microemulsion as binder and containing simvastatin (SV) as model drug. The effects
of the variables were determined by evaluating the granule median diameter, their particle size distribution,
roundness, disintegration time and dissolution rate of SV. Results clearly demonstrated that the
microemulsion-based process was less sensitive tooperating conditions than the water-based process.
With microemulsion the nucleation process and growth regimes were more difficult to control, resulting
in products with broader PSDs. At the same operatingconditions microemulsion-based granules were
more brittle but rounder and showed smaller median diameter compared to water-based granules. The
dissolution rate of simvastatin was not significantly affected by the operating conditions
