Survival Outcomes Following Autologous Stem Cell Transplant with Melphalan 140mg/m Versus 200mg/m Preparative Regimens in Patients with Multiple Myeloma

The standard preparative regimen for autologous stem cell transplant (ASCT) in multiple myeloma (MM) is 200 mg/m of intravenous melphalan; however, a dose of 140 mg/m is often used when concerns exist related to patient age, performance status, organ function, and other factors. It is unclear whether a lower dose of melphalan impacts post-transplant survival outcomes. We performed a retrospective review of 930 patients with MM who underwent ASCT with 200 mg/m versus 140 mg/m melphalan. On univariable analysis, no difference in progression-free survival (PFS) was observed, however, an overall survival (OS) benefit was observed in patients receiving 200 mg/m melphalan ( = 0.04). Multivariable analyses showed patients receiving 140 mg/m faired no worse than those receiving 200 mg/m. While a subset of younger patients with normal renal function may achieve superior OS with a standard dose of 200 mg/m melphalan, these findings suggest an opportunity to individualize the ASCT preparative regimen to optimize outcomes.