The present invention relates to a method of treating multiple myeloma in a subject comprising administering to the subject an amount of (1) a compound of formula (I), as described herein, and/or a stereoisomer, tautomer, or pharmaceutically acceptable salt thereof, and an amount of (2) dexamethasone and/or a pharmaceutically acceptable salt, solvate, metabolite or racemate thereof, such that the subject is treated. In another aspect, provided herein is a method of treating multiple myeloma in a subject comprising administering to the subject an amount of (1) a compound of formula (I) and an amount of (2) dexamethasone, such that the subject is treated pharmaceutical formulations comprising said combination for the treatment of multiple myelom and compositions thereof.