Monoclonal Antibody CT-011 in Combination With Rituximab in Patients With Relapsed Follicular Lymphoma

Inclusion Criteria:

1. Patients with histologic proof of follicular lymphoma grade 1 or grade 2 relapsing after at least 1 but no more than 4 prior systemic therapies.Patients may have had prior local radiation therapy in addition to up to 4 prior systemic therapies. History of total body irradiation will be considered as prior systemic therapy.
2. If patient received prior rituximab-based therapy, should have rituximab sensitive disease defined as a complete or partial response of at least 6 months duration with the rituximab-based regimen.
3. Patients must be \>= 18 years of age.
4. Should have measurable (\>= 1.5 cm) disease.
5. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
6. At least 4 weeks from last chemotherapy, immunotherapy, radiation therapy, monoclonal antibody therapy, or experimental therapy and must have recovered from acute toxic effects of prior therapy.
7. Absolute neutrophil count \>= 1.5 × 10\^9/L.
8. Platelets \>= 50 × 10\^9/L.
9. Absolute lymphocyte count \>= 0.6 × 10\^9/L.
10. Adequate renal function with creatinine \<= 1.5 × the upper limit of normal (ULN).
11. Adequate hepatic function with total bilirubin \<= 1.5 mg/dL; AST and ALT \<= 2.5 × ULN.
12. Women of child-bearing potential (i.e., woman has not been naturally postmenopausal for at least 24 consecutive months or not surgically sterile) and sexually active men must agree to use 2 acceptable contraceptive methods during this study. One of the 2 methods of birth control must be a condom. Acceptable methods of birth control in combination with condoms include diaphragm, birth control pills, injections, intrauterine device, and/or under-the-skin implants. Men and women must agree to maintain effective contraception for up to 3 months after the last dose of drug is administered.
13. Patients must sign an informed consent indicating that they are aware of the investigational nature of this study.

Exclusion Criteria:

1. Patients positive for HIV, hepatitis B surface antigen, or hepatitis C antibody.
2. Patients requiring concurrent immunosuppressive therapy are excluded. Inhaled or topical steroids for treating mild to moderate respiratory illnesses, allergies, skin rashes or ocular inflammations are allowed.
3. History of central nervous system (CNS) lymphoma.
4. Active or history of autoimmune disease except Hashimoto's thyroiditis. Patients with type I diabetes mellitus are excluded.
5. Active infection or other serious intercurrent medical illness
6. New York Heart Association Class III or IV disease.
7. Pregnant or nursing.
8. History of allogeneic stem cell transplantation.
9. Other concurrent chemotherapy, radiotherapy, immunotherapy, or investigational therapy
10. Any other malignancy except basal or squamous cell carcinoma of the skin, or cervical carcinoma in situ treated with curative intent. Any cancer from which the patient has been disease free for at least 5 years is permissible.
11. Any underlying medical condition which, in the Principal Investigator's opinion, will make the administration of study drug hazardous or obscure the interpretation of adverse events.