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Defeating cancer with radiopharmaceutical medicines

Despite therapeutic advances made in the last decade, there remains a high unmet need for new cancer treatments. Radiation therapy is a proven approach to treating many cancers and is typically administered by an external beam of high energy rays. In contrast, radiopharmaceuticals selectively deliver radioisotopes to tumors via the bloodstream.


Radiopharmaceuticals have the unique advantage of being both diagnostic and therapeutic. The same drug conjugate could be used for both diagnostic imaging and therapeutic use by switching out the radioisotope. Direct visualization of drug conjugate uptake by tumors with imaging allows for proper patient selection to receive the therapeutic radioisotope (e.g. Actinium-225).

RayzeBio is sponsoring the phase 1/3 ACTION-1 study for patients who have inoperable, progressive, somatostatin receptor positive (SSTR+) gastroenteropancreatic neuroendocrine tumors (GEP-NET). 

The trial is a part of larger international study and will compare the standard of care therapy with 225Ac-DOTATATE (RYZ101). The phase 1 portion of the study will look at the safety and tolerability of RYZ101.

The phase 1 of the study is currently enrolling at sites across the country.

Main Eligibility Criteria:

  • Over 18 years of age

  • Grade 1-2 well differentiated GEP-NET (GI or pancreas)

  • Ki67 <= 20%

  • Progressive GEP-NET following 2 to 4 cycles of treatment with 177Lu-DOTATATE / 177Lu-DOTATOC. If 177Lu-DOTATATE or 177Lu-DOTATOC treatment was stopped before completing 4 cycles, it should not have been stopped early due to disease progression.

  • Must have had some response to PRRT, defined as tumor shrinkage or tumor stability, that lasted at least 3 months following the last dose of prior 177Lu-DOTATATE/DOTATOC

  • No prior treatment with alkylating agents

  • No prior use of anticancer agents within the following intervals prior to the first dose of study drug:

    • Peptide Receptor Radionuclide Therapy (PRRT): within <8 weeks

    • Chemotherapy: within <6 weeks

    • Small molecule inhibitors: within <4 weeks

    • Biological agents: within <7 days or <5 half-lives

  • No prior external radiation therapy, including stereotactic body radiation therapy (SBRT)

  • No prior radioembolization treatment

  • No significant cardiovascular disease

  • No known brain metastases

If you are interested in learning more, please ask your doctor to contact


Samuel Mehr, MD
Nebraska Cancer Specialists
Omaha, NE

Michael Morris, MD, MS
Advanced Molecular Imaging and Therapy
Glen Burnie, MD

Daneng Li, MD
City of Hope
Duarte, CA

For more information, contact

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PM-US-AZ-0552       06/2022

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