RecruitingEarly Phase 1Drug trialA Phase 0/1 Clinical Trial With an Expansion Phase of GSK5764227, a B7-H3-Targeted Antibody-Drug Conjugate (ADC), in Patients With Recurrent Grade 4 Glioma and Patients With Brain MetastasesThis will be an open-label Phase 0/1 study that will enroll approximately 15 participants, 9 participants with recurrent WHO Grade 4 glioma (rGBM) and 6 participants with brain metastases, who will receive the investigational drug risvutatug rezetecan (GSK5764227), a B7-H3-targeted antibody-drug conjugate (ADC) with the GSK5757810 payload. The trial will consist of a Phase 0 component (subdivided into Arms A and B) and an Expansion Phase 1 component. Participants with tumors demonstrating a positive pharmacokinetic (PK) response in the Phase 0 component will be eligible to enroll in the Expansion Phase to receive therapeutic dosing of risvutatug rezetecan.