A Study of PLX2853 in Advanced Malignancies.

Inclusion Criteria: * Confirmed diagnosis of one of the following: * Phase 1b: * Histologically confirmed advanced refractory solid tumor that is measurable or evaluable per RECIST 1.1 criteria. * Histologically confirmed NHL: diffuse large B-cell lymphoma and follicular lymphoma (Grade 1-3A) which is measurable or evaluable per Lugano criteria, has progressed following at least 1 line of prior anticancer therapy. * Phase 2a: Patients with various solid tumors or NHL who have received prior therapy. * Age ≥18 years * Eastern Cooperative Oncology Group (ECOG) performance status 0 to 1 * Adequate organ function as appropriate for the disease under study. All screening laboratory tests should be performed within 10 days of treatment initiation. * Women of child-bearing potential (WOCBP) must have a negative serum pregnancy test at Screening (≤7 days prior to 1st study drug dose) and must agree to use an effective form of contraception from the time of the negative pregnancy test up to 90 days after the last dose of study drug. Effective forms of contraception include abstinence, hormonal contraceptive in conjunction with a barrier method, or a double barrier method. Women of non-child-bearing potential may be included if they are either surgically sterile or have been postmenopausal for ≥1 year. * Fertile men must agree to use an effective method of birth control during the study and for up to 90 days after the last dose of study drug. * All associated clinically significa…