Substudy 01A: Zilovertamab Vedotin in Pediatric and Young Adult Participants With Hematologic Malignancies or Solid Tumors (MK-9999-01A/LIGHTBEAM-U01)

To join this study, participants must be between 6 months and 25 years old. They need to have a confirmed diagnosis of certain blood cancers (like B-precursor B-cell acute lymphoblastic leukaemia or specific types of diffuse large B-cell lymphoma and Burkitt lymphoma) or solid tumours (like neuroblastoma or Ewing sarcoma).

There are also some reasons why someone might not be able to join. For example, if they have had an organ transplant, a serious heart condition, severe liver disease, or certain nerve problems (like ongoing peripheral neuropathy or Charcot-Marie-Tooth disease). Individuals with Down syndrome or active graft-versus-host disease (GVHD) would also not be eligible.

Other reasons for not being able to take part include having HIV, an allergy to any part of the study drug, or recent treatments like radiotherapy within the past four weeks (until all side effects have cleared). Certain other medications, like high doses of steroids or specific strong drugs that affect liver enzymes, could also prevent participation. Recent live vaccinations or other anti-cancer treatments within the last four weeks would also make someone ineligible.

The study involves receiving the investigational medication, Zilovertamab Vedotin. The exact schedule of visits and assessments would be fully explained by the study team. This would typically include regular check-ups, blood tests, and scans to monitor your health and how the treatment is working. You would need to inform the study team about all medications you are taking and any symptoms you experience. The total duration of participation would be outlined by the study team, including how long you would receive the treatment and any follow-up appointments after that.