Tafasitamab and Zanubrutinib for the Treatment of Patients With Newly Diagnosed Chronic Lymphocytic Leukemia or Small Lymphocytic Lymphoma, TaZA CLL Study

This phase II trial tests how well tafasitamab and zanubrutinib works in treating patients with newly diagnosed chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). Tafasitamab is a monoclonal antibody that may interfere with the ability of cancer cells to grow and spread. Zanubrutinib is in a class of medications called kinase inhibitors. It works by blocking the action of a protein that signals cancer cells to multiply. This may stop the growth and spread of cancer cells. Giving tafasitamab and zanubrutinib in combination may kill more cancer cells in patients with CLL/SLL than giving either treatment alone.

PRIMARY OBJECTIVES: I. To evaluate the safety/tolerability of tafasitamab and zanubrutinib (as assessed by unacceptable toxicity) in patients with newly diagnosed CLL. (Safety lead-in) II. To evaluate the anti-tumor activity of tafasitamab and zanubrutinib as assessed by complete response (CR) rate per International Workshop on CLL (iwCLL) 2018 criteria in patients with newly diagnosed CLL. (Phase 2) SECONDARY OBJECTIVES: I. To assess the toxicity of the combination of tafasitamab and zanubrutinib through evaluation of toxicities. II. To obtain estimates of overall response rate (ORR), progression-free survival (PFS), and duration of response (DOR). III. To assess the undetectable minimal residual disease (uMRD) rate in response to tafasitamab and zanubrutinib. EXPLORATORY OBJECTIVES: I. To assess the effect of tafasitamab and zanubrutinib combination on immune function of T cells and NK cells. II. To explore mechanisms of resistance to the combination of tafasitamab and zanubrutinib. III. To investigate the association of established biomarkers (chromosomal abnormalities, immunoglobulin heavy chain \[IGHV\] mutational status, TP53 mutational status) with response (ORR and PFS) to tafasitamab and zanubrutinib in patients with CLL. OUTLINE: This is a dose-escalation study of zanubrutinib followed by a phase II study. Patients receive tafasitamab intravenously (IV) and zanubrutinib orally (PO) on study. Patients also collection of blood samples on study and undergo computed tomography (CT) scan and bone marrow biopsy throughout the trial.