We propose to develop a novel therapy for multiple myeloma using a polymer that contains antibody recognizing a surface marker of myeloma. The antibody will deliver two drugs sole to myeloma. One is doxorubicin, a chemotherapy drug frequently used in myeloma, and the other is HA14-1, a novel small molecular compound that blocks the cell death inhibitor Bcl-2. The efficacy of the polymers will be studied in the animal model that mimics the bone marrow environment of myeloma. Finally, the therapeutic effect will be furher enhanced by combining with bortezomib, a highly potent agent for myeloma.