Rituxan/Bendamustine/PCI-32765 in Relapsed DLBCL, MCL, or Indolent Non-Hodgkin's Lymphoma

PRIMARY OBJECTIVES: I. Identify the specific toxicities and a recommended phase 2 dose of PCI-32765 (BTK inhibitor PCI-32765) orally (PO) in combination with rituximab and bendamustine (bendamustine hydrochloride) (i.e., "combination therapy") in patients with relapsed and refractory B-cell NHL. SECONDARY OBJECTIVES: I. Evaluate the activity of combined rituximab, bendamustine, and PCI-32765 in patients with relapsed and refractory B-cell NHL as measured by response rate and duration of response. II. Identify potential marker(s) predictive of response to the combination therapy. III. Correlate pharmacogenetic (PGx) findings with patient response and toxicity. OUTLINE: This is a dose-escalation study of BTK inhibitor PCI-32765. Patients receive BTK inhibitor PCI-32765 PO once daily (QD) on days 1-28. Patients also receive rituximab intravenously (IV) on day 1 and bendamustine hydrochloride IV over 30 minutes on days 1-2. Treatment repeats every 28 days for up to 6 courses in the absence of disease progression or unacceptable toxicity. Patients may continue receiving BTK inhibitor PCI-32765 PO in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up at 30 days and then every 4 months for up to 2 years.