Deterioration of the swallowing function in elderly persons and drug refusal among the behavioral abnormalities in Alzheimer's disease (AD) are commonly reported. Therefore, we developed an easy-to-swallow jelly formulation of Donepezil HCl which AD patients can take as a dessert. The development process, however, was full of trade-oŠ problems.(1) Need for evaluating the taste of a drug product vs. Safety of human sensory evaluation of the taste. The trade-oŠ was resolved by using a taste sensor. (2) Speed of development vs. Safety of the manufacturing process. We put priority on the safety rather than speed, and a safer antioxidant agent was found. (3) Usability of the container for AD patients with dysphagia vs. Size of the container. We put priority on its being user-friendly rather than on the size and chose a stable wide-mouth cup. (4) Suitable texture of jelly for swallowing the drug product vs. Residual volume of jelly in the cup. We designed the texture so that the residual volume of jelly in the cup was reduced. (5) Easy peeling properties of aluminum seal vs. High sealing strength for sterilization. The sealing strength was adjusted so that it was adequate to sterilize the drug product. (6) One cup in a heat-sealed aluminum pillow package to prevent overdose vs. Seven cups in a pillow package. A single-dose package was relatively expensive, but it was chosen to assure safety. We faced many di‹cult trade-oŠ problems in the development of process. However, they were resolved using technical innovations and a people-friendly policy. Finally, we were able to launch a novel oral jelly formulation for elderly patients.

Using a taste sensor in theˆeld of medical products has the following four main purposes: (1) Ensuring that investigational product and placebo are indistinguishable; (2) Formulation design; (3) Quality control; (4) Benchmark test. Unlike evaluating a taste of food, roughly predicting a taste of drug without human sensory test and quantitative evaluation using small quantity of drug sample are more important than evaluation of the nuances of homogeneous taste and preference. Here are some examples of using taste sensor for these purposes. (1) We predicted a taste of suspension of phosphatic drug substance in an early phase of development using a taste sensor. As a result, the suspension seemed to have sour and bitter taste. Then we made placebo solution of citric acid similar taste as much like active suspension to ensure indistinguishable taste from each other. (2) A taste of orally disintegrating tablet (ODT) in the mouth is important to drug adherence. The taste of an ODT was then evaluated in chronological order by combining the taste sensor with the new disintegration testing apparatus to design easy-to-take formulation. (3) We evaluated taste variation of a commercial product in batch-to-batch and identiˆed the cause of the variation. (4) We did benchmark test for easy-totake of commercial ODTs in vitro. There is great variability among these products in the disintegrating proˆle and the taste.