A Phase I Study of CLR 131 in Children, Adolescents, and Young Adults with Recurrent or Persistent Solid Tumors, Lymphoma, and Brain Tumors


Full Title

An Open-Label, Dose Escalation, Efficacy, and Safety Study of CLR 131 in Children, Adolescents, and Young Adults with Select Solid Tumors, Lymphoma, and Malignant Brain Tumors (CLOVER-2) and Expansion in Children, Adolescents and Young Adults with Relapsed or Refractory High-Grade Glioma (WCG)


The purpose of this study is to find the highest dose of the investigational drug CLR 131 that can be given safely in children, adolescents, and young adults with solid tumors, lymphoma, or malignant brain tumors that came back or continued to grow despite treatment. CLR 131 is a targeted form of radiotherapy. It gives off cancer-killing doses of radiation to tumor tissue while limiting the effects of radiation on surrounding normal tissues and organs.

Patients in this study will either receive a single dose of CLR 131 or the same amount divided into two doses given two weeks apart. CLR 131 is given intravenously (by vein).

Who Can Join

To be eligible for this study, patients must meet several criteria, including but not limited to the following:

  • Patients must have a pediatric solid tumor (such as neuroblastoma or sarcoma), lymphoma, or malignant brain tumor that has come back or continued to grow despite prior treatment.
  • At least 2 weeks must pass between the completion of prior treatment and receipt of CLR 131.
  • Cancer treatment can lower blood cell counts. Patients must have some of their own stem cells already banked (frozen) so they can be returned to them after treatment to make new blood cells. Stem cells are unspecialized human cells that can develop into many different cell types. If a patient does not have banked stem cells, some stem cells will be collected as part of the study, before the patient receives CLR 131. 
  • Patients must be able to walk and do routine activities for more than half of their normal waking hours.
  • This study is for patients older than age 2 years and younger than 25.

For more information about this study and to inquire about eligibility, please contact 1-833-MSK-KIDS.




Phase I (phase 1)

Disease Status

Newly Diagnosed & Relapsed/Refractory


ClinicalTrials.gov ID