PRIMARY OBJECTIVES:~Test the safety and feasibility of isatuximab-based drug treatment.~Evaluate the preliminary efficacy of a slow-go approach in high risk AL amyloid patients.~STUDY TREATMENT~Each patient starts by receiving increasing intensity of treatment for AL Amyloidosis up to maximum tolerance, and then maintenance Isatuximab thereafter for a specified period.~All patients will receive Isatuximab (weekly x 4 then every other week) plus dexamethasone 4 mg PO/IV days weekly. If tolerating Isatuximab/Dex4 (earliest time to escalate C1D15), add Velcade to 1 mg/m2 SQ weekly. If tolerating Isa/Vel1.0/Dex4 (earliest time to escalate C2D1), increase dexamethasone to 12 mg weekly. If tolerating Isa/Velcade1.0/Dex12 (earliest time to escalate C3D1), increase Velcade to 1.3 mg/m2 SQ. If tolerating Isa/Velcade1.3/Dex12 (earliest time to escalate C4D1), add cyclophosphamide 300 mg IV weekly. If tolerating Isa/Velcade1.3/Cy300/Dex12 (earliest time to escalate C5D1), increase cyclophosphamide to 400 mg IV weekly. If tolerating Isa/Velcade1.3/Cy400/Dex12 (earliest time to escalate C6D1), increase cyclophosphamide to 500 mg IV weekly.~Tolerance determined by the patient not reaching an escalation limiting toxicity AND patient approval to dose escalate.~Patients then receive dexamethasone and isatuximab as maintenance treatment twice per month for 12 months in the absence of disease progression or unacceptable toxicity.
This phase I trial studies the side effects of isatuximab and to see how well it works in treating patients with high risk immunoglobulin light chain amyloidosis (AL amyloidosis). Isatuximab is a monoclonal antibody that may interfere with the ability of tumor cells to grow and spread.