Background/Objectives: To improve the therapeutic efficacy of albendazole (ABZ) for
ileocolonic diseases, its low solubility at higher pH levels should be enhanced. Organic
acids have been widely used as pH modifiers to improve the solubility of weakly basic
drugs. To achieve an adequate effect of the acidic microenvironmental pH during the
drug release, pH modifiers should not leach out from the formulation. In the present
work, we aimed to demonstrate that 100% tartaric acid pellets (TAP) can be used as
pH-modifier cores, providing an acidic microenvironmental pH to enhance the solubility
of albendazole at a higher pH. Methods: This study develops multilayer-coated pellets
using TAP as starter cores in a bottom-spray-configured fluidized bed apparatus. The
drug-layered TAP were coated with time-dependent and pH-dependent layers. Results:
The release of ABZ from tartaric acid-based coated pellets was enhanced compared to
that from pellets with the same layering structure but with an inert core of sugar
or microcrystalline cellulose (MCC). In vitro experiments showed that tartaric acid
remained in the pellet core during the dissolution test at a pH 6.8 medium, which
resulted in an enhanced release of albendazole at a higher pH. The application of
a combination of time-dependent and pH-dependent polymers aimed not only to prevent
the release of albendazole at lower pH levels but also to protect TAP from premature
release from the formulation. Conclusions: The application of 100% ready-to-use tartaric
acid pellets (TAP) with the applied combination of coatings enhanced the solubility
of the weakly basic drug albendazole at higher intestinal pH.
