Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Efficacy of AMG 562 in Subjects With r/r Diffuse Large B-cell Lymphoma, Mantle Cell Lymphoma, or Follicular Lymphoma

Inclusion Criteria: * Subject has provided informed consent prior to initiation of any study-specific activities/procedures * Age ≥ 18 at the time of informed consent. * Biopsy proven B-NHL including: * DLBCL, which also includes DLBCL that represents transformation of indolent NHL (including follicular, marginal zone, and lymphoplasmacytic lymphoma excluding chronic lymphocytic leukemia or Hodgkin Lymphoma) and DLBCL with alterations of MYC and BCL2 and/or BCL6 also described as double-hit and triple-hit lymphomas. * FL * MCL Presentations of these histologies with substantial occurrence of malignant cells into the bloodstream (lymphocyte count ≥ 7 x 10\^9/L) including all leukemic presentations are excluded. The following histologies are not eligible: Lymphoblastic lymphoma Burkitt lymphoma Any histologies not specifically mentioned must be discussed with the Medical Monitor * Subjects with transformation of indolent lymphoma must have received therapy after a diagnosis of transformation that is appropriate for aggressive histology. \- Subjects who received prior CD19-targeting treatment are allowed (CAR-T cell therapy is excluded). A biopsy following CD19-targeting treatment is required unless no lesions are accessible or the risk of the biopsy is deemed too high by the investigator For Part 2 (Expansion in patients with DLBCL): only biopsy proven DLBCL (biopsy proven at least at primary diagnosis), including DLBCL that represents transformation of indolent N…