Provided herein are methods of using 4-(4-(4-((2-(2, 4-difluorophenyl)-1, 2 The present invention relates to a method of treating, preventing or managing multiple myeloma in combination with a first active agent, a second active agent, or an enantiomer, enantiomer mixture, tautomer, or pharmaceutically acceptable salt thereof. The present invention also relates to a method of treating, preventing or managing multiple myeloma in combination with a first active agent and an enantiomer, enantiomer mixture, tautomer, or pharmaceutically acceptable salt thereof, or an enantiomer, enantiomer mixture, tautomer, or pharmaceutically acceptable salt thereof. The second active agent is one or more of a BTK inhibitor, an mTOR inhibitor, a PIM inhibitor, an IGF-1R inhibitor, an MEK inhibitor, an XPO1 inhibitor, a DOT1L inhibitor, an EZH2 inhibitor, a JAK2 inhibitor, a BRD4 inhibitor, a PLK1 inhibitor, an NEK2 inhibitor, an AURKB inhibitor, a BIRC5 inhibitor, a BET inhibitor or a DNA methyltransferase inhibitor.