Bioequivalence study of improved modified formulation of cilostazol 100 mg orally disintegrating tablet and currently marketed cilostazol 100 mg orally disintegrating tablet (Pletaal® OD tablet 100 mg) in healthy adult male subjects

The cilostazol orally disintegrating tablet currently on the market (current ODT) was developed as a tablet for easier use in patients with difficulty of swallowing water. Cilostazol improved modified formulation orally disintegrating tablet (improved ODT) is a newly-developed formulation that dissolves in the oral cavity more quickly than the current ODT. The bioequivalence of one cilostazol 100 mg improved ODT and one cilostazol 100 mg current ODT, each taken with or without water, was evaluated in healthy adult male subjects in an open-label, randomized, 2-formulation, 2-treatment, 2-period crossover study. A total of 44 subjects were enrolled and 38 subjects completed the study. When administered without water, the differences in the mean log-transformed AUC_60h, and C_max values between the improved ODT and the current ODT (improved ODT-current ODT, point estimates) were respectively log (0.91) and log (1.03), with respective 90% confidence intervals of log (0.84) to log (0.98) and log (0.93) to log (1.15). When administered with water, the differences in the mean log-transformed AUC _60h and C_max values between the improved ODT and the current ODT were both log (0.95), with respective 90% confidence intervals of log (0.89) to log (1.02) and log (0.83) to log (1.08). All values were within the range of the equivalence judgment criteria of log (0.8) to log (1.25) specified in the guideline for bioequivalence studies. Based on these results, one cilostazol 100 mg improved ODT was judged to be bioequivalent to one cilostazol 100 mg current ODT when administered either with or without water. All adverse events observed in either group were mild or moderate in severity, and other than one case of influenza, all adverse events were resolved without treatment. There were no deaths or other serious adverse events.