Ofatumumab for High-Risk Chronic Lymphocytic Leukemia (CLL)/Small Lymphocytic Lymphoma (SLL)

The Study Drug: Ofatumumab is designed to bind to the surface of some of the white blood cells (B-cells). It may destroy cancer cells that come from B-cells. Study Drug Administration: If you are found to be eligible to take part in this study, you will receive a "loading dose" (a lower dose given first, to lower the risk of a bad reaction to the study drug) of ofatumumab by vein on Day 1 of Cycle 1. The loading dose is less than one-third (1/3) of the normal dose. You will then receive the normal dose over 4 hours 1 time each week (+/- 3 days). The doses may be given more slowly, if your doctor thinks it is needed. All doses of the study drug will be given at M. D. Anderson. Benadryl (diphenhydramine) and glucocorticoids (steroids such as prednisolone) will be given by vein 30 minutes to 2 hours before you receive ofatumumab to help prevent side effects. You will also take pills of acetaminophen (Tylenol) to help prevent side effects. If no side effects occur, these "pre-medications" may be reduced or not given after the second infusion. Study Visits: One (1) time each week, before you receive ofatumumab: * You will have a physical exam, including measurement of your vital signs. * You will be asked about how you are feeling, about any side effects you may be having, and about any changes in your health since the last visit. * Blood (about 2 teaspoons) will be drawn for routine tests. Length of Study: You may continue taking the study drug until Day 50, as long as the doctor thinks it is in your best interest. You will no longer be able to take the study drug if the disease gets worse, if intolerable side effects occur, if you develop hepatitis B, or if you decide to go off study. End-of-Treatment Visit: On the day of your last treatment or after you stop receiving the study drug for any reason, the following tests and procedures will be performed: * You will have a physical exam, including measurement of your vital signs. * You will be asked about how you are feeling, about any side effects you may be having, and about any changes in your health since the last visit. * Blood (about 2 teaspoons) will be drawn for routine tests. * If the doctor thinks it is needed, blood (about 2 teaspoons) will be drawn for hepatitis testing. Follow-Up: About 3 months (+/- 2 weeks) after the end-of-treatment visit, the following tests and procedures will be performed: * You will have a physical exam, including measurement of your vital signs. * You will be asked about how you are feeling, about any side effects you may be having, and about any changes in your health since the last visit. * You will have a bone marrow aspirate and biopsy, as well as CT scans of the chest, abdomen, and pelvis, to check the status of the disease. * Blood (about 2 teaspoons) will be drawn for routine tests. * If the doctor thinks it is needed, blood (about 2 teaspoons) will be drawn for hepatitis testing. Every 3 months (+/- 4 weeks) after the end-of-treatment visit for 6 months: * You will have a physical exam, including measurement of your vital signs. * You will be asked about how you are feeling, about any side effects you may be having, and about any changes in your health since the last visit. * Blood (about 2 teaspoons) will be drawn for routine tests. * If the doctor thinks it is needed, blood (about 2 teaspoons) will be drawn for hepatitis testing. Every year (+/- 4 weeks) after the end-of-treatment visit: * You will have a physical exam, including measurement of your vital signs. * You will be asked about how you are feeling, about any side effects you may be having, and about any changes in your health since the last visit. * Blood (about 2 teaspoons) will be drawn for routine tests. * You will have a bone marrow aspirate and biopsy, as well as CT scans of the chest, abdomen, and pelvis, to check the status of the disease. This is an investigational study. Ofatumumab is FDA approved and commercially available for use in the treatment of CLL. The use of ofatumumab as an early treatment for patients with CLL/SLL who have not received other treatment is investigational. Up to 44 patients will take part in this study. All will be enrolled at MD Anderson.