Bortezomib-based induction therapy followed by intravenous busulfan-melphalan as conditioning regimen for patients with newly diagnosed multiple myeloma.

A bortezomib-containing regimen followed by high-dose therapy and autologous stem cell transplant (ASCT) is considered the standard of care for front-line therapy in younger patients with newly diagnosed multiple myeloma (MM). We analyzed the results of ASCT with an intravenous busulfan 9.6 mg/kg and melphalan 140 mg/m2 (ivBUMEL) preparative regimen in 47 patients with newly diagnosed MM who had received bortezomib-based combinations as pre-transplant induction. The overall response rate and complete response after transplant were 100% and 49%, respectively. With a median follow-up of 24.5 months, median overall survival and progression-free survival have not been reached. Mucositis and febrile neutropenia were the most frequent toxicities observed. No case of sinusoidal obstruction syndrome was observed and there was no transplant-related mortality. These results suggest that front-line induction therapy with a bortezomib-based combination followed by ASCT with ivBUMEL is an effective and well-tolerated therapeutic approach for transplant eligible patients with MM.