MIRA-1 is a maleimide-derived small molecule that reactivates the tumor suppressor function of mutant p53, inducing apoptosis in several human solid tumor cell lines carrying tetracycline-regulated mutant p53 (IC50 = 10 μM in vitro).1 Treatment of tumor cells with MIRA-1 induces p21, MDM2 and PUMA in a mutant p53-dependent manner.[1] At a concentration of 5-10 mg/kg, MIRA-1, alone or in combination with dexamethasone , arrested tumor growth in a mouse xenograft model of multiple myeloma.[2]