Patients with AL amyloidosis can present with a wide range of general symptoms that are common to other conditions such as fatigue, shortness of breath or edema. Current treatment strategies target plasma cells to reduce production of new light chain proteins, but do not address the amyloid already deposited in vital organs. Mortality is driven primarily by cardiac failure. There is an urgent unmet medical need for therapies that improve survival in patients at risk for early mortality due to amyloid deposition. Based on clinical data to date, Mayo Stage IV patients represent approximately 30% of AL amyloidosis patients.