BACKGROUND: Thalidomide is an immunomodulatory drug with strong antimyeloma activity. It is an effective treatment for multiple myeloma at disease recurrence and at diagnosis, both as a single agent and in combination with steroids or chemotherapy. No data are available on the association of thalidomide with oral melphalan and prednisone, still considered the standard treatment for elderly patients. METHODS: The feasibility and efficacy of the combination of melphalan, prednisone, and thalidomide (MPT) have been valuated in 49 newly diagnosed patients with multiple myeloma. RESULTS: According to European Bone Marrow Transplantation/ International Bone Marrow Transplantation Registry (EBMT/IBMTR) criteria, 18% of patients achieved immunofixation-negative complete disease remission (CR), 6% achieved immunofixation-positive near CR, 4% achieved a very good partial response, and 45% achieved a partial response, with a 50-89% reduction in monoclonal paraprotein. Six percent did not respond and 10% showed progressive disease. The median time to maximum response was 4 months. The Kaplan-Meier estimates of event-free survival and overall survival at 2 years were 64% and 91%, respectively. The major acute adverse events (National Cancer Institute Common Toxicity Criteria Grade III-IV) included thrombosis (20%), infections (12%), constipation (6%), and hematologic (22%) and neurologic (8%) toxicities. One patient died of pulmonary thromboembolism. CONCLUSIONS: These data suggested that MPT induced rapid and durable tumor responses with CR rates similar to those observed after autologous transplantation. Administration of prophylactic anticoagulant was required to prevent thromboembolism. MPT merits further investigation in randomized clinical trials.