Last reviewed 2026-04-23 · How we verify

Sm-153

Sm-153 is a radioactive isotope used for targeted radiation therapy.

Sm-153 is a radioactive isotope used for targeted radiation therapy. Used for Pain relief in bone metastases.

At a glance

Mechanism of action

Sm-153 emits beta radiation that selectively targets cancer cells, causing cell death. This targeted approach minimizes damage to surrounding healthy tissue.

Approved indications

• Pain relief in bone metastases

Common side effects

• Bone marrow suppression
• Nausea and vomiting
• Fatigue

Key clinical trials

• Samarium Optimized for Long-lasting Analgesia in Cancerous End-stage Bone Pain (PHASE1)
• Samarium-153 With Neoadjuvant Hormonal and Radiation Therapy for Locally Advanced Prostate Cancer (PHASE1)
• Zoledronate, Vitamin D, and Calcium With or Without Strontium 89 or Samarium 153 in Preventing or Delaying Bone Problems in Patients With Bone Metastases From Prostate Cancer, Lung Cancer, or Breast Cancer (PHASE3)
• A Dose Finding Study to Treat Bone Tumor(s) (PHASE1)
• Prospective REgistry of Targeted RadionucLide TherapY in Patients With mCRPC (REALITY Study)
• A Dose Finding Study of CycloSam® Combined With External Beam Radiotherapy (PHASE1)
• Repeated Bone Marrow Transplantation in Treating Women With Advanced Breast Cancer (PHASE1, PHASE2)
• Samarium Sm 153 and Stem Cell Transplant Followed By Radiation Therapy Patients With Osteosarcoma (PHASE2)

Primary sources

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