The US Food and Drug Administration approved Lymphoseek. Lymphoseek is a radioactive diagnostic imaging agent. It will allow doctors to evaluate the spread of squamous cell carcinoma in the body’s head and neck region.
Lymphoseek is currently marketed by Navidea, a biopharma company based in Dublin, OH.
It is important to identify lymph nodes in cancer because they filter fluid that drains from tissue. If the tissue is cancerous, the fluid will contain cancer cells. Testing lymph nodes allows doctors to determine if the cancer has spread.
The approval of Lymphoseek for use in the head and neck of cancer patients means that doctors will be able to use the agent to guide testing lymph nodes closest to a primary tumor (sentinel nodes). According to the FDA, the guided testing will allow for the option of more limited lymph node surgery in patients.
For some patients with head and neck cancer an important diagnostic evaluation is removal and pathological examination of lymph nodes draining a primary tumor.
Lymphoseek contains tiny radioactive molecules that are designed to bind to receptors discovered in high concentrations on the surface of cells located in lymph nodes.
In order to use Lymphoseek doctors must inject it into the tumor area and use a handheld gamma counter to find the sentinel lymph nodes that have taken up the radioactive molecules.
Before approval, the FDA reviewed a clinical trial that tested the drug’s safety and effectiveness in 85 patients with squamous cell carcinoma of the lip, oral cavity and skin.
The trial compared Lymphoseek against conventional tumor location and surgical practices. The trial found that Lymphoseek accurately determined if the cancer had spread through the lymphatic system.
The trial also found that the most common side effects were pain or irritation at the injection site.
