The United States Patent and Trademark Office has granted Chunghwa Chemical Synthesis & Biotech Co. Ltd. “CRYSTAL FORM B OF RIBOCICLIB SUCCINATE” (US 10336763 B1) on July 2, 2019.

The invention provides the new crystal forms of Ribociclib succinate, an active pharmaceutical ingredient(API) for breast cancer drug, and a preparation method thereof, more specifically a new crystal form B. Form B has low hygroscopicity and thermal stability under high humidity conditions, ensuring that the drug is not easily converted to other crystal forms during storage and transportation, which is advantageous for industrial production.