Acalabrutinib and Obinutuzumab for the Treatment of Previously Untreated Follicular Lymphoma or Other Indolent Non-Hodgkin Lymphomas

PRIMARY OBJECTIVE: I. To determine if treatment acalabrutinib and obinutuzumab is effective in patients with untreated, low tumor burden follicular lymphoma and other indolent non-Hodgkin lymphomas (NHLs). SECONDARY OBJECTIVES: I. Determine the complete response (CR) rate for single agent acalabrutinib at the end of a single-agent run-in for patients with untreated low tumor burden follicular lymphoma (FL). II. Determine tolerability of acalabrutinib and obinutuzumab via assessment of patient-reported outcomes and conventional assessments. III. Assess duration of response and long-term outcomes including progression-free survival. IV. Assess the impact of early treatment with this regimen on health-related quality of life. TERTIARY/EXPLORATORY OBJECTIVES: I. Evaluate the impact of treatment discontinuation in patients who have achieved a complete response at the end of the induction phase. II. To assess the safety and efficacy of acalabrutinib and obinutuzumab in other subtypes of indolent NHL. OUTLINE: INDUCTION PHASE: Patients receive acalabrutinib orally (PO) twice daily (BID) on days 1-28. Patients also receive obinutuzumab intravenously (IV) on days 1, 8, and 15 of cycle 3, then on day 1 of cycles 4-8. Treatments repeat every 28 days for up to 12 cycles in the absence of disease progression or unacceptable toxicity. FOLLOW-UP PHASE: After cycle 12, patients who are in CR are randomized to either discontinue acalabrutinib or to continue acalabrutinib monotherapy in the absence of disease progression or unacceptable toxicity. Patients with partial response (PR) or stable disease (SD) after cycle 12 continue acalabrutinib monotherapy in the absence of disease progression or unacceptable toxicity. Patients with disease progression after cycle 12 discontinue study treatment. Patients with disease progression at any time prior to the conclusion of cycle 12 may continue study therapy if they are felt to be benefiting by the treating physician, but not past cycle 12. After completion of study treatment, patients are followed up at 30 days, every 12 weeks for 1 year, then every 6 months until disease progression or next anti-lymphoma treatment.