This is a brief overview of information related to FDA’s approval to market this product. See the links below to the Summary of Safety and Effectiveness Data (SSED) and product labeling for more complete information on this product, its indications for use, and the basis for FDA’s approval.
Product Name: TheraSphere™
PMA Applicant: Boston Scientific Corporation
Address: 11 Hines Road, Suite 200, Ottawa, CAN K2K 2X1 Ontario
Approval Date: March 17, 2021
Approval Letter: Approval Letter
What is it?
TheraSphere is a radiation treatment for people who have a specific type of liver cancer called unresectable hepatocellular carcinoma (HCC). TheraSphere consists of millions of microscopic glass spheres containing yttrium-90. Yttrium-90 is used in radiation therapy to treat certain forms of cancer. The TheraSphere Yttrium-90 Glass Microsphere System contains:
- a sterile, single use, dose vial of TheraSphere Y-90 Glass Microspheres;
- a sterile, single-use TheraSphere Administration Set; and
- a non-sterile, re-usable TheraSphere Administration Accessory Kit.
How does it work?
TheraSphere is delivered to the cancer tissue (tumor) in the liver through a catheter in an artery. Radiation from the Yttrium-90 helps treat the tumor. This approach delivers the radiation carried by the spheres only to the region containing the tumor and minimizes the effects of radiation in normal tissues outside of the tumor. Within 12 days of treatment, approximately 95% of the radiation from Yttrium-90 in the glass spheres is absorbed into the region containing the tumor. The glass spheres stay in the liver permanently.
When is it used?
TheraSphere is used to treat unresectable HCC tumors that are 1-8 cm in diameter in patients with mild cirrhosis or asymptomatic cirrhosis. It is also used to treat people with unresectable HCC whose cancer has not progressed.
What will it accomplish?
Therasphere may help control liver cancer by shrinking the tumor or stopping it from getting bigger. In a clinical study of 162 people, 117 of them experienced a partial or complete response (tumor shrinking). For 89 of the patients, the response lasted for at least six months before the tumor started to grow again.
When should it not be used?
TheraSphere should not be used in people:
- In whom the TheraSphere would enter organs other than the liver, based on information from a pre-treatment scan,
- In whom a catheter cannot be placed safely in the artery leading to the liver,
- Who have poor blood flow to the heart or poor liver function,
- Who have certain types of blockage of the portal vein (a blood vessel that carries blood from the gastrointestinal tract, gallbladder, pancreas, and spleen to the liver),
- Who have a tumor in more than 70% of the liver,
- Who have other medical problems or poor overall health that may make them a poor candidate for TheraSphere treatment, or
- Who are pregnant.