Velcade®, Thalidomide, Dexamethasone (VTD) Induction Therapy Followed by Melphalan, Prednisone, Thalidomide (MPT) Maintenance as a First Line Treatment for the Patients (pts) with Multiple Myeloma (MM) Who Are Non-Transplant Candidates: Early Analysis from the Korean Multiple Myeloma Working Party.

VTD and MPT chemotherapies have been known to be active regimens in pts with MM. The objective of this study is to examine response and toxicities and to estimate survival of pts with VTD followed by MPT, who are non-transplant candidates with previously untreated MM. Total of 29 pts were enrolled from March, 2006 through August, 2007 and this study is still ongoing. 13 pts were men and 16 pts were women. The median age was 67 years (range, 61–75 years) and median follow up was 5 months (range, 1–16 months). Here 23 pts who completed at least first two cycles of VTD were analyzed. Pts received bortezomib (Velcade®) 1.3 mg/m² on days 1, 4, 8, 11, thalidomide 100 mg daily, dexamethasone 40 mg on days 1–4 every 3 weeks for a maximum of 6 cycles of treatment, and thereafter melphalan 4 mg/m² on days 1–7, prednisone 40 mg/m² days 1–7, thalidomide 100 mg daily every 4 weeks for a maximum of 12 cycles. In these 23 pts, 92% of them showed responses (18% CR, 4% nCR, and 70% PR). 17 pts completed 4 cycles of VTD and all of them showed 100% response rates (CR 35%, nCR 18%, PR 47%). 13 out of 14 who completed 6 cycles of VTD showed responses (CR 50%, nCR 14%, PR 29%, PD 7%). It is too early to see whether improved response rate translates into improved overall survival (OS) and progression free survival (PFS). The median OS and PFS have not been reached yet. 11 pts (37%) stopped protocol therapy because of consent withdrawal (2 pts), death (4 pts), disease progression (2 pts) and severe adverse reaction (3 pts). The causes of death were infection-related in 2 pts who had been in remission. Other 2 pts were related to disease progression. Although peripheral neuropathy affected all of pts, only 20% of the pts were grade 3. The most common side effects of the chemotherapies greater than grade 3 were pneumonia (24%), asthenia (12%), diarrhea (16%), nausea (4%), thrombocytopenia (16%), neutropenia (12%) and anemia (12%). Although VTD followed by MPT chemotherapy in pts with previously untreated MM, who are non-transplant candidates showed high response rates with manageable toxicities, they showed high withdrawal rates from the study which attributed partly to the characteristics of the pts at baseline who were non-transplant candidates because of old age and morbidities, and a few major neuropathies. Follow up data will be presented.