AZD6244 (Selumetinib) in Treating Patients With Multiple Myeloma

PRIMARY OBJECTIVES: I. To assess the response rate of AZD6244 (selumetinib) hydrogen sulfate capsules in patients with relapsed or refractory multiple myeloma (MM). SECONDARY OBJECTIVES: I. To evaluate the toxicity of AZD6244 in patients with MM. II. To estimate progression-free survival and duration of response to AZD6244. III. To test whether AZD6244 hydrogen sulfate capsules downregulate tumor cell phosphorylated mitogen-activated protein kinase (pERK)1/2. OUTLINE: Patients receive selumetinib orally (PO) twice daily (BID) on days 1-28. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up every 6 weeks.