A Study of SGN-35 (Brentuximab Vedotin) of Patients With Relapsed or Refractory PMLBCL

Study Objectives Primary: • To determine the antitumor efficacy of single-agent Brentuximab vedotin (1.8 mg/kg administered intravenously every 3 weeks) as measured by the overall objective response rate in patients with relapsed or refractory primary mediastinal large B-cell lymphoma. Secondary: * To assess duration of tumor control, including duration of response and progression-free survival * To assess survival * To assess the safety and tolerability of Brentuximab vedotin Additional: • To assess disease-related symptoms Number of Planned Patients 20 patients will be enrolled in this study. Duration of the study The study duration is 18 months for enrollment and 2 years for the follow-up.