............. 51 7.3 Treatment Assignment and Stratification ................................ ................................ .................... 51 7.4 Study Drug Handling and Accountability ................................ ................................ ................... 51 7.4.1 Preparation ................................ ................................ ................................ ........................... 51 7.4.2 Labeling ................................ ................................ ................................ ............................... 51 7.4.3 Storage ................................ ................................ ................................