European Trial of Free Light Chain Removal by Extended Haemodialysis in Cast Nephropathy

Inclusion Criteria: * Age \>= 18 years * Dialysis dependent acute renal failure (eGFR \<15ml/min/1.73m2) * Fulfils diagnostic criteria for the diagnosis of symptomatic de novo multiple myeloma1 * Abnormal serum FLC ratio and a sFLC concentration \> 500 mg/L * Myeloma kidney demonstrated on a renal biopsy (cast nephropathy) * Ability to give informed consent to partake in study * Commencement of study within 10 days of presenting to enrolling unit Exclusion Criteria: * Age \< 18 years * Known advanced chronic renal failure (CKD stage IV 4-5; eGFR \<30mls/min/1.73m2) or evidence of significant chronic damage on renal biopsy * Amyloidosis or light chain deposition disease on renal biopsy * Previous treatment of multiple myeloma with chemotherapy * Haemodynamic instability that precludes unsupported dialysis renal replacement therapy * Significant cardiac disease (myocardial infarction with in the last 6 months; unstable angina; NYHA class III or IV heart failure; clinically significant pericardial disease; cardiac amyloidosis) * Advanced disease or significant co-morbidity: with poor short term prognosis, necessitating palliation and no active or disease specific treatment. * Inability to give informed consent * History of allergic reaction attributable to compounds containing boron or mannitol * History of Peripheral neuropathy or neuropathic pain (grade 2 or higher as defined by NCI CTCAE version 3) * Clinically significant liver dysfunction (bilirubin \>1.8mg/dl (30µmol/L)) * Known HIV infection * Active uncontrolled infection * Pregnant and lactating women * Inability to give informed consent * Pre-menopausal female patients of childbearing potential: positive pregnancy test or unwilling to use effective contraception during the study * Lactation