A First-in-Human, phase 1, Open-Label, dose escalation and expansion study evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of BG-T0920 in DLBCL and other aggressive B-Cell malignancies

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Confirmed diagnosis of any of the below according to World Health Organization (WHO) classification 1. Diffuse large B-cell lymphoma, not otherwise specified (DLBCL-NOS) 2. Diffuse large B-cell lymphoma / high-grade B-cell lymphoma (DLBCL/HG-BCL) with MYC and BCL2 rearrangements 3. High-grade B-cell lymphoma, not otherwise specified (HG-BCL, NOS) 4. Large B-cell lymphoma (LBCL) transformed from an antecedent indolent B-cell lymphoma (BCL), including Follicular lymphoma (FL) and marginal zone lymphoma (MZL) * Must have relapsed or refractory disease with no other available therapies with established clinical benefit (including anti-CD20-based immunochemotherapy, autologous stem cell transplant \[if eligible\], chimeric antigen receptor T-cell therapy (CAR-T) \[if eligible\], or T-cell engager (TCE) therapy) that would be more appropriate in the investigator's judgment. * Must have measurable disease by computed tomography (CT)/ magnetic resonance imaging (MRI), defined as at least 1 lymph node \> 1.5 cm in the longest diameter or 1 extranodal lesion \> 1.0 cm in the longest diameter, measurable in 2 perpendicular dimensions. * Must have an Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 to 2. Exclusion Criteria: * Prior autologous stem cell transplant \< 100 days before first dose of the study drug. * Prior allogenic transplant or solid organ transplant at any time in the past. * Known or suspected progressive multifocal leukoencephalopathy. * Known or suspected history of hemophagocytic lymphohistiocytosis (HLH). * Recent prior therapies, prior to the first dose of study drug: 1. Biologic-based anti-lymphoma therapy (eg, monoclonal antibodies, antibody-drug conjugates, radioimmunoconjugate, or T-cell engager therapy (TCE) within 28 days 2. CAR-T therapy within 90 days 3. Systemic chemotherapy or small-molecule targeted therapy (investigational or otherwise) within 28 days or 5 half-lives (whichever is shorter) 4. Systemic corticosteroids in excess of 25 mg/day prednisone (or equivalent) within 14 days. Inhaled, topical, or systemic corticosteroids at doses of ≤ 25 mg/day prednisone (or equivalent) are permitted. 5. Radiation therapy within 14 days. If a patient has undergone radiation therapy since last progression, at least one measurable lesion must be outside the radiation field 6. T-cell suppressive therapy (eg, alemtuzumab, fludarabine) within 6 months, unless discussed with the medical monitor. * History of severe allergic reactions or hypersensitivity to the active ingredient or excipients of BG-T0920 or other monoclonal antibodies. * Unable to comply with the requirements of the protocol, unless the written approval of the medical monitor has been obtained before informed consent. * Active significant infection (bacterial, viral, fungal, parasitic) at study enrollment, or any Grade 3 or 4 infection requiring treatment with Intravenous (IV) systemic therapy or hospitalization within 4 weeks prior to the first dose of the study drug. Note: Oral antimicrobial therapy used for minor or controlled infections or for prophylactic purposes is allowed. Note: Other protocol defined Inclusion/Exclusion criteria may apply.