A Study of RP-3500 in Combination with Standard Radiation Therapy to Treat Symptoms in People with Metastatic Solid Tumors


Full Title

RP-3500 (ATRi) + External Beam Radiotherapy (EBRT) for the Palliative Treatment of Metastatic Disease


Mutations in a gene called ATM affect the way cancer cells repair damage caused by radiation therapy. External beam radiation therapy (EBRT) is often given to relieve symptoms such as pain (“palliative therapy”) in people with metastatic cancer and to slow cancer growth. In this study, researchers are finding the highest dose of the investigational drug RP-3500 that can be given safely in combination with EBRT as palliative therapy for people with metastatic cancers containing an ATM mutation.

RP-3500 blocks a protein called ATR, which also repairs damage to cancer cells. Researchers believe that using RP-3500 to block ATR in people whose cancer has a mutated ATM gene may make cancer cells unable to survive the damage caused by EBRT. RP-3500 is taken orally (by mouth).

Who Can Join

To be eligible for this study, patients must meet several requirements, including:

  • Participants must have a metastatic solid tumor that contains an ATM mutation and who will be receiving palliative EBRT.
  • The serious side effects of prior therapies must go away before receiving the study treatment.
  • Patients must be able to walk and do routine activities for more than half of their normal waking hours.
  • This study is for people age 18 and older.


For more information and to ask about eligibility for this study, please contact the office of Dr. Nancy Lee at 212-639-3341.




Phase I/II (phases 1 and 2 combined)

Disease Status

Newly Diagnosed & Relapsed/Refractory


ClinicalTrials.gov ID