Federal Register Notice FDA has determined the regulatory review period for Zevalin (CD20 Monoclonal Antibody) is 3,363 days for the extension of a patent which claims that human biological product. Zevalin is indicated for treatment of patients with relapsed or refractory low-grade, follicular, or transformed B-cell non-Hodgkin's lymphoma, including patients with Rituximab (Rituxan) refractory follicular non-Hodgkin's lymphoma. To view this notice, click here.