Characterization of haematological parameters with bortezomib-melphalan-prednisone versus melphalan-prednisone in newly diagnosed myeloma, with evaluation of long-term outcomes and risk of thromboembolic events with use of erythropoiesis-stimulating agents: Analysis of the VISTA trial

Although haematological toxicities, such as anaemia, are common in multiple myeloma (MM), no clear consensus exists on the use and impact of erythropoiesis-stimulating agents (ESA) on outcomes in MM. This analysis characterizes haematological toxicities and associated interventions in the phase III VISTA (Velcade ^® as Initial Standard Therapy in Multiple Myeloma: Assessment with Melphalan and Prednisone) study of bortezomib plus melphalan/prednisone (VMP, n=344) versus MP (n=338) in previously untreated MM patients ineligible for high-dose therapy, and evaluates the impact of ESA use or red-blood-cell (RBC) transfusions on outcomes and thromboembolic risk. Incidence of haematological toxicities was similar with VMP and MP; similar rates of interventions and associated complications (e.g. bleeding, febrile neutropenia) were observed. Two hundred thirty three patients received ESA; 204 had RBC transfusions. Frequency of thromboembolic events was low and not affected by ESA use. Median time-to progression (TTP) was similar between ESA/non-ESA [hazard ratio: 1·03 (95% confidence interval 0·76-1·39); P=0·8478] in both arms (VMP: 19·9/not reached; MP: 15·0/17·5months). Three-year overall survival (OS) rates were similar between ESA/non-ESA in each arm. Patients receiving RBC transfusions had significantly shorter OS (P<0·0001) versus non-RBC-transfusion patients. In conclusion, bortezomib did not add to melphalan haematological toxicity. Concomitant ESA use with VMP/MP in previously untreated MM patients did not adversely affect TTP or OS, or increase thromboembolic risk. However, RBC transfusion was associated with significantly shorter survival.