CRYSTALLINE FORM OF PITAVASTATIN CALCIUM

摘要

PROBLEM TO BE SOLVED: To provide a production method of new crystalline forms of a pitavastatin hemicalcium salt which are useful to hypercholesterolemia.SOLUTION: The production method for a crystal polymorphism A (Fig.1: X-ray powder diffraction pattern) of a pitavastatin hemicalcium salt (formula) comprises allowing a sodium salt of pitavastatin to react with CaClin an aqueous reaction medium, separating a formed crystal, and drying it so that the water content is adjusted to 3-12%.