Single Agent Obinutuzumab in Relapsed/Refractory Post-Transplant Lymphoproliferative Disorder (PTLD)

Patients with post transplant lymphoproliferative disorder (PTLD) that have been treated with at least one type of chemotherapy, but whose lymphoma is not responding or coming back after the previous treatment will be asked to participate in this study.

This clinical trial uses a drug called Obinutuzumab. The Food and Drug Administration (FDA) has approved Obinutuzumab for sale in the United States for certain diseases. Obinutuzumab is still being studied in clinical trials to learn more about what its side effects are and whether or not it is effective in the disease or condition being studied. Obinutuzumab is considered an investigational drug in this study

Obinutuzumab (GA101) is an antibody directed against cluster of differentiation antigen 20 (CD20). Antibodies are protein that are part of the immune system that can target cancer cells. Obinutuzumab sticks to a target called CD20. CD20 is an important molecule on some cancer cells (including non-Hodgkin lymphoma) and some normal cells of the immune system.

This study is being done to test if the study drug has an effect on post transplant lymphoproliferative disorder and to see how lymphoma will respond to the study drug.

Primary Objective:

• To determine the overall response rate of obinutuzumab in relapsed/refractory post-transplant lymphoproliferative disorder (PTLD) in both solid organ transplant (SOT) and bone marrow transplant (BMT) patients

Secondary Objectives:

* Complete remission (CR) rate
* Duration of response (DOR)
* Progression free survival (PFS)
* Overall survival (OS)
* Time to treatment failure (TTF)
* Safety and tolerability of obinutuzumab

Patient Population:

Relapsed or refractory post-transplant lymphoproliferative disorder (PTLD) patients who have received at least one prior therapy

Study Design:

Phase II study of single agent obinutuzumab in relapsed/refractory (RR) post-transplant lymphoproliferative disorder (PTLD) in both SOT and BMT patients

Eligibility Criteria:
Inclusion Criteria:

* Histologically or cytologically confirmed relapsed/refractory post-transplant lymphoproliferative disorder
* Relapsed/refractory disease with at least 1 prior chemotherapy regimen
* Measurable disease ≥1.5 cm
* Eastern Cooperative Oncology Group (ECOG) performance status of 0-2. ECOG 3 will be permitted if the decline in the performance status is attributed to the lymphoma
* Able to sign the consent form
* Adequate organ function

  * bilirubin ≤1.5 times upper limit of normal (ULN), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤2.5 times ULN or ≤5 times ULN for patients with document hepatic involvement with lymphoma
  * serum creatinine clearance \>50 ml/min
  * absolute neutrophil count (ANC) ≥500/μL (unless documented bone marrow involvement with lymphoma)
  * hemoglobin \>8 gm/dl
  * platelet count ≥50,000/μL (unless documented bone marrow involvement with lymphoma)

Exclusion Criteria:

* Prior treatment with obinutuzumab
* Pregnancy or breast feeding women
* Current active malignancy other than PTLD, requiring active treatment
* Presence of central nervous system (CNS) involvement
* HIV positive patients
* Myocardial infarction within the past 6 months
* Patients with the following medical conditions that could affect their participation in the study:

  * any active acute or chronic or uncontrolled infection
  * liver disease including history of viral hepatitis B or C, evidence of cirrhosis, chronic active or persistent hepatitis
  * a known history of HIV
  * symptomatic cardiac disease, including congestive heart failure, coronary artery disease, and arrhythmias
* Current therapy with chemotherapy or investigational agents within 4 weeks of start of study treatment