The goal of this clinical trial is to learn if drug GSK5926371 works to treat a form of B-cell cancer (a type of blood cancer) that has returned or failed to respond to prior therapies in adults. The study will primarily assess the drugs safety and tolerability in participants. Additionally, it seeks to determine the clinical efficacy and pharmacokinetic (PK) properties of GSK5926371.
Has histologically confirmed Relapsed/Refractory (R/R) B-NHL, for which systemic treatment is indicated,
Has measurable disease,
Has received at least 2 prior lines of systemic anti-neoplastic therapy, including an anti-CD20-containing combination appropriate for the indication;
Willing to use adequate contraception (Participant of childbearing potential [POCBP] only).
Has a malignancy (except disease under study) that has progressed or required active treatment within the past 24 months except for basal cell or squamous cell carcinomas of the skin or in-situ carcinomas (e.g., breast, cervix, bladder) that have been resected with no evidence of metastatic disease.
Has had any major surgery within 4 weeks prior to the first dose of GSK5926371 or has not recovered from prior surgeries or complications.
Has a history of Progressive multifocal leukoencephalopathy (PML), current central nervous system (CNS) involvement by lymphoma, or a history of significant CNS disease such as uncontrolled seizures, stroke, epilepsy, CNS vasculitis, and neurodegenerative conditions.
Has an active uncontrolled infection.