A novel fine granule system for masking bitter taste

In order to prepare fine granules of sparfloxacin (SPFX), a new quinolone anti-bacterial drug that shows masking of the bitter taste of SPFX and dissolutes at a rapid rate, various film-coated fine granules containing 20% SPFX and 0-52% low-substituted hydroxypropylcellulose(L-HPC) in the cores, were prepared by a spray method. Mixtures of ethylcellulose (EC), hydroxypropylmethylcellulose (HPMC), titanium dioxide and sucrose stearate in weight ratios of X:Y:2:1 (X + Y = 6) were used as film materials. The degree of masking of the bitter taste by water-insoluble film, mainly consisting of EC and HPMC, increased by increasing the content ratio of EC to HPMC and the amount of films, but was also slightly affected by the amount of L-HPC in the cores, which were coated with either EC or EC/HPMC (4/2). On the other hand, the dissolution rate increased with an increased amount of L-HPC in the cores and with a decreasing ratio of EC to HPMC in the films. Increasing the amount of L-HPC in the cores, which induced a considerable expansion of the fine granules owing to their taking up of water from the dissolution medium, resulted in bursting of the film after a short lag time. The bioavailability of the film-coated fine granules containing 20% SPFX and 52% L-HPC in the cores and 10% EC/HPMC (4/2) in the coating film, which masked the bitter taste of SPFX and showed the optimal release characteristics, was equivalent to that of conventional tablets containing 100 mg SPFX in beagle dogs.