The mechanical strength, particle size and sphericity of starting sugar spheres for drug layering and subsequent functional coating applications are critical to achieving a reproducible and high yield final product. During early processing, spheres can be subjected to high mechanical stress that may result in the generation of fines, changes in particle size and loss of sphericity. The European Pharmacopoeia describes both a fluidization apparatus and an oscillating apparatus method for determining the

friability of granules and spheroids. The oscillating method was shown by Christiansen et. al. to be more suitable for consistently determining the friability of pellets over a wide range of hardness. These friability methods however may not be fully indicative of mechanical stresses in a production environment. The objective of this study was to evaluate the mechanical robustness of SUGLETS® sugar spheres using the oscillating friability method as compared to attrition values generated in laboratory and production scale fluid bed processes.