TheraSphere® is a powerful*, well-tolerated liver cancer therapy that consists of millions of small glass microspheres (20 to 30 micrometers in diameter, or about a third of the width of a human hair) containing radioactive yttrium-90. The product is injected by physicians into the artery of the patient’s liver through a catheter, which allows the treatment to be delivered directly to the tumor via blood flow.
This approach provides a high concentration of radiation treatment directed to the tumor, and limits both damage to surrounding healthy tissue and side effects for the patient that often result from other forms of cancer treatment, such as external radiation or systemic therapy. This form of radioembolization therapy also keeps future treatment options open as patients progress through the later stages of their disease.
In the US, TheraSphere® is used to treat patients with hepatocellular carcinoma (HCC) who can have appropriately positioned hepatic arterial catheters, and can be used as a bridge to surgery or transplantation in these patients. It is also indicated for the treatment of HCC patients with partial or branch portal vein thrombosis or occlusion when clinical evaluation warrants the treatment. TheraSphere® is approved by the U.S. Food and Drug Administration (FDA) under a Humanitarian Device Exemption (HDE). HDE approvals are based on demonstrated safety and probable clinical benefit. However, effectiveness of the indication for use has not been established.
*Refers to high specific activity.