Inclusion Criteria:

• Subjects with histologically confirmed chronic lymphocytic leukemia (CLL), small lymphocytic lymphoma (SLL), prolymphocytic leukemia (PLL) as defined by WHO classification of hematopoietic neoplasms, or Richter's transformation arising out of CLL/SLL and satisfying ≥ 1 of the following conditions:
• Progressive splenomegaly and/or lymphadenopathy identified by physical examination or radiographic studies
• Anemia (<11 g/dL) or thrombocytopenia (<100,000/μL) due to bone marrow involvement
• Presence of unintentional weight loss > 10% over the preceding 6 months
• NCI CTCAE Grade 2 or 3 fatigue
• Fevers > 100.5 degree or night sweats for > 2 weeks without evidence of infection
• Progressive lymphocytosis with an increase of > 50% over a 2 month period or an anticipated doubling time of < 6 months
• Need for cytoreduction prior to stem cell transplant

• Subjects must have failed ≥ 2 prior therapies for CLL including a nucleoside analog or ≥ 2 prior therapies not including nucleoside analog if there is a contraindication to such therapy

  •> 10% expression of CD20 on tumor cells

• ECOG performance status ≤ 2
• Life expectancy ≥ 12 weeks
• Subjects must have organ and marrow function as defined below:

Absolute neutrophil count (ANC) ≥ 1000/µL in the absence of bone marrow involvement Platelets ≥ 30,000/μL Total bilirubin ≤ 1.5 x institutional upper limit of normal unless due to Gilbert's disease AST(SGOT) ≤ 2.5 x institutional upper limit of normal unless due to infiltration of the liver Creatinine ≤ 2.0 mg/dL OR creatinine clearance ≥ 50 mL/min

• No history of prior anaphylactic reaction to rituximab
• No history of prior exposure to ofatumumab
• Age ≥ 18 years
• Body weight ≥ 40 kg
• Able to swallow capsules without difficulty and no history of malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction

Exclusion Criteria:

• A life-threatening illness, medical condition or organ system dysfunction which, in the investigator's opinion, could compromise the subject's safety, interfere with the absorption or metabolism of PCI-32765 PO, or put the study outcomes at undue risk
• Any anticancer immunotherapy, chemotherapy, radiotherapy, or experimental therapy within 4 weeks before first dose of study drug. Corticosteroids for disease-related symptoms are allowed provided 1 week washout occurs.
• Active central nervous system (CNS) involvement by lymphoma
• Major surgery within 4 weeks before first dose of study drug
• Lactating or pregnant
• History of prior malignancy, except for adequately treated basal cell or squamous cell skin cancer, in situ cervical cancer, or other cancer from which the subject has been disease free for at least 2 years or which will not limit survival to < 2 years
• History of Grade ≥ 2 toxicity (other than alopecia) continuing from prior anticancer therapy