In the development of 2-[[[2-[(hydroxyacetyl)amino] -4-pyridinyl]methyl]thio]-N-[4-(trifluoromethoxy)phenyl]-3- pyridinecarboxamide (compound (A)), there exist several complex problems: (1) compound (A) or salts thereof are difficult of recrystallization, said salts being considerably different in storage stability, and it is very difficult to obtain a salt of compound (A) having high storage stability (2) in the crystallization process of compound (A), the control of polymorphism is very difficult (3) compound (A) (in the free form) causes mineral deposition in the stomach when oral-administered repeatedly and so on. In order to solve the problems, studies have been made with attention being paid to the kinds of salts. As a result, it has been found that benzensulfonate (salt) of compound (A) has the following properties: (1) in a one-week preliminary stability test (severe test), benzensulfonate of compound (A) is not decomposed by light, humidity, or other factors, thus being unproblematic in storage stability (2) two kinds of crystal forms are prsent, and the crystal forms can be selectively produced by a certain method and (3) no mineral deposition in the stomach is observed even after four-week repeated oral administration.Durante el desarrollo de la 2- [[[2 - [(hidroxiacetil) amino]- 4 -piridinil] metil] tio]- N -[4 -(trifluorometoxi) fenil]- 3 -piridincarboxamida (compuesto A), existen múltiples problemas: 1) el compuesto A o su sal son difíciles de re-cristalizar, la estabilidad de almacenamiento difiere en gran parte dependiendo del tipo de sal y es muy difícil obtener una sal del compuesto A que tenga excelente estabilidad de almacenamiento 2) en un proceso de cristalización del compuesto A, es muy difícil controlar un cristal polimorfo y 3) el compuesto A (puro) causa deposición mineral en el estómago cuando es administrado repetidamente por vía oral. Para resolver estos problemas, se hizo un examen enfocándose en el tipo de sal y, como resultado, se enc
