Study of BGB-11417 in Adult Participants With Mature B-cell Malignancies

The purpose of this study is to evaluate the safety and tolerability of BGB-11417 monotherapy, define the maximum tolerated dose (MTD) or maximum administered dose and the recommended Phase 2 dose (RP2D) of BGB-11417 monotherapy for the selected B-cell malignancy dose finding cohorts, and evaluate the safety and tolerability of the ramp-up dosing schedule in the evaluated disease types.

This study will have 3 cohorts for determining a monotherapy MTD and ramp-up schedule: Cohort A, participants with relapsed/refractory B-cell non-Hodgkin lymphoma (R/R NHL); Cohort B, participants with R/R chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) with low tumor burden; Cohort C, participants with R/R CLL/SLL with high tumor burden.

Key Inclusion Criteria: 1. Confirmed diagnosis of only one of the following: Cohort A a. Marginal Zone Lymphoma i. R/R extranodal, splenic or nodal disease defined as disease that has relapsed after, or been refractory to, ≥ 1 line of anti-CD20 antibody-based chemoimmunotherapy for ≥ 2 consecutive cycles, and no effective standard therapy for MZL is available per investigator's assessment. ii. Active disease requiring treatment. b. Follicular Lymphoma i. R/R FL (Grade 1, 2 or 3a based on the WHO 2008 classification of tumors of hematopoietic and lymphoid tissue) and defined as disease that has relapsed after, or been refractory to, ≥ 1 line of anti-CD20 antibody-based chemoimmunotherapy for ≥ 2 consecutive cycles, and no effective standard therapy for FL is available per investigator's assessment. ii. Active disease requiring treatment. c. Diffuse Large B-cell Lymphoma i. R/R DLBCL defined as disease that relapsed after, or been refractory to, at least one line of anti-CD20 antibody based chemoimmunotherapy for ≥ 2 consecutive cycles, and no effective standard therapy for DLBCL is available per investigator's assessment. ii. Active disease requiring treatment. d. Transformed indolent B-cell NHL i. Any lymphoma otherwise eligible for Cohort A that has transformed into a more aggressive lymphoma. Patients with transformation from CLL or SLL (Richter's transformation) are not eligible for Cohort A. ii. Active disease requiring treatment. Cohorts B and C a. CLL/SLL diagnosis that meets the International Workshop on Chronic Lymphocytic Leukemia (IWCLL) criteria: i. R/R disease defined as disease that has relapsed after, or been refractory to, ≥ 1 line of standard therapy for ≥ 2 consecutive cycles, and no effective standard therapy is available per investigator's assessment. ii. Requiring treatment based on IWCLL criteria. 2. Measurable disease by computed tomography/magnetic resonance imaging, defined as: 1. CLL: At least 1 lymph node \> 1.5 centimeters (cm) in longest diameter and measurable in 2 perpendicular dimensions. For Cohort B, participants should not meet with the definition of high tumor burden, which is required for participants enrolled in Cohort C. 2. DLBCL, FL, MZL, SLL: At least 1 lymph node \> 1.5 cm in longest diameter OR 1 extranodal lesion \> 1.0 cm in the longest diameter, measurable in 2 perpendicular dimensions. For MZL isolated splenomegaly is considered to indicate measurable disease for this study. For SLL, participants in Cohort B should not meet with the definition of high tumor burden, which is required for participants enrolled in Cohort C. Key Exclusion Criteria: 1. Prior malignancy (other than the disease under study) within the past 2 years, except for curatively treated basal or squamous cell skin cancer, superficial bladder cancer, carcinoma in situ of the cervix or breast, or localized Gleason score ≤ 6 prostate cancer. 2. Underlying medical conditions that, in the investigator's opinion, will render the administration of study drug hazardous or obscure the interpretation of safety or efficacy results. 3. Known central nervous system involvement by lymphoma/leukemia. 4. Known plasma cell neoplasm, prolymphocytic leukemia, history of or currently suspected Richter's syndrome. 5. Prior autologous stem cell transplant unless ≥ 3 months after transplant; or prior chimeric cell therapy unless ≥ 6 months after cell infusion. 6. Prior allogeneic stem cell transplant.