Polatuzumab Vedotin in Combination With Chemotherapy in Subjects With Richter's Transformation

This study evaluates the effectiveness and safety of Polatuzumab vedotin plus infusional chemoimmunotherapy containing rituximab, etoposide, prednisone, cyclophosphamide and hydroxydaunorubicin. This is a single arm study. Enrolled patients will receive up to six cycles (21-day cycles) of therapy. While on study, subjects will be monitored weekly until end of treatment, then followed for 52 weeks or until disease progression or discontinuation due to toxicity or death. After completion of the 52-week follow-up/End of study visit, Subjects will be followed for an additional 104 week period, with an assessment occurring every 12 weeks to evaluate survival outcomes and next line of treatments only.