After mixing 50.6 mg of S-309309 hydrate (as 50 mg of S-309309) with 10 mg of a watersoluble polymer (HPC, HPMC, or PVP), the flat tablets consisting of each mixture were prepared using a single tablet press equipped with a 7.5 mm diameter at a compression force of 5 kN. A drop of water (1 µL) was dropped onto the flat surface of each tablet and then the water contact angle was measured using an automatic contact angle meter (DMo-601; Kyowa Interface Science Co., Ltd. Niiza, Saitama, Japan). The control group consisted of tablets containing only S-309309, without a water-soluble polymer.