TheraSphere® 90Y glass microspheres deliver high doses of radiation to liver tumors while sparing normal tissue.  The result is a powerfully-targeted, well-tolerated therapy that may lead to patients becoming eligible for curative therapies.

TheraSphere® is used in selective internal radiation therapy (SIRT), a procedure in which glass microspheres containing radioactive 90Y are delivered to the tumor vasculature via transfemoral catheterization of the hepatic artery. TheraSphere® capitalizes on the uniquely organized dual blood supply to the liver, which occurs through the hepatic artery and the portal vein. In liver cancer, tumor blood supply is almost exclusively (80–100%) from the hepatic artery. In contrast, normal liver tissue receives most of its blood flow (75%) from the portal vein.

Treatment with TheraSphere® has been optimized to minimize unnecessary radiation exposure through the packaging of the dose vial, use of the Administration Accessory Kit and the radiation dose delivery mechanism.

TheraSphere® is suitable for patients in whom either the liver is the only site of disease or the liver is the major site of disease. The effects of TheraSphere® on tumors outside the liver has not yet been studied.

TheraSphere® treatment has some common side effects that may occur throughout the first week after treatment, including mild to moderate fatigue, pain and nausea. Physicians describe these symptoms as similar to those of the common flu. Some patients may experience loss of appetite and temporary changes in liver blood tests.