⁃ Men and women aged ≥18 years.

⁃ Disease as defined below:

⁃ Part 1: Patients with symptomatic CLL or SLL (defined by iwCLL) without del(17p)/TP53 must have received ≥2 prior therapies that have included a BTKi and venetoclax (or declined this) or Patients with progressive low-grade lymphoma that includes marginal zone lymphoma, lymphoplasmacytic lymphoma (including Waldenstrom's macroglobulinemia) who have received at least 2 therapies including a BTKi and CD20 antibody-based therapy.

⁃ Part 2: Patients with symptomatic CLL or SLL (defined by iwCLL) must have received ≥1 prior therapies that have included a BTKi and be venetoclax naive.

⁃ Prior to beginning part 2, an activation amendment will be submitted to the FDA that includes safety, pharmacokinetics, pharmacodynamics and early efficacy data from the Part 1 portion. At this time, we may also include cohorts of specific types of low-grade lymphoma as well. Adequate bone marrow, liver, and renal functions as assessed by the following laboratory requirements to be conducted within 7 days before the first dose of study drug:

∙ Absolute neutrophil count (ANC) \> 0.75 x 109/L. For subjects with documented bone marrow involvement ≥ 0.5 x 109/L

‣ Platelet count \> 50 x 109/L. For subjects with documented bone marrow involvement ≥ 30 x 109/L

‣ Serum aspartate transaminase (AST/SGOT) or alanine transaminase (ALT/SGPT) ≤ 3.0 x upper limit of normal (ULN)

‣ Total bilirubin ≤ 1.5 x ULN

‣ Creatinine or Cystatin C glomerular filtration rate (GFR) ≥60 mL/min. Estimated GFR (eGFR) according to the Modification of Diet in Renal Disease Study Group (MDRD) formula and expressed in mL/min. To convert mL/min/1.73 m2 to mL/min multiply by the individual's BSA calculated using an appropriate formula and divide by 1.73 Eastern Cooperative Oncology Group (ECOG) performance status of 2 or less Negative serum or urine pregnancy test must be obtained within 7 days before the first dose of study drug in women of childbearing potential. Negative results must also be available before each cycle.

• Postmenopausal women, as defined below, are exempt from pregnancy testing:

• Age \>50 years with amenorrhea for at least 12 months or

• Age ≤50 years with 6 months of spontaneous amenorrhea and follicle stimulating hormone (FSH) level within postmenopausal range (\>40 mIU/mL) OR

• Permanently sterilized women (e.g., hysterectomy, bilateral salpingectomy, or uterine ablation) Women and men of reproductive potential must agree to use highly effective contraception when sexually active. This applies for the period between signing of the informed consent and 90 days after the last administration of study drug. These methods should be documented in source documents. The investigator or a designated associate is requested to advise the subject on how to achieve highly effective birth control. Ability to understand and the willingness to sign a written informed consent. A signed informed consent (including consent for genetic biomarker