FDA Approves Lymphoseek Imaging Agent

The FDA has approved Lymphoseek (technetium Tc 99m tilmanocept) Injection imaging agent that helps doctors locate lymph nodes in patients with breast cancer or melanoma who are undergoing surgery to remove tumor-draining lymph nodes.

Lymphoseek, marketed by Navidea Biopharmaceuticals, Inc. in Dublin, Ohio, is the first new drug used for lymph node mapping to be approved in more than 30 years, according to the FDA. Other approved drugs include sulfur colloid (in 1974) and isosulfan blue (in 1981).

“Removal and pathological examination of lymph nodes draining a primary tumor is an important diagnostic evaluation for some patients with breast cancer or melanoma,” Shaw Chen, MD, deputy director of the Office of Drug Evaluation IV in the FDA’s Center for Drug Evaluation and Research, said in a statement. “To use Lymphoseek, doctors inject the drug into the tumor area and later, using a handheld radiation detector, find lymph nodes that have taken up Lymphoseek’s radioactivity.”

Lymphoseek’s safety and effectiveness were established in two clinical trials of 332 patients with melanoma or breast cancer. Patients were injected with Lymphoseek and blue dye, another drug used to help locate lymph nodes. Surgeons then removed suspected lymph nodes for pathologic examination. Confirmed lymph nodes were examined for their content of blue dye and/or Lymphoseek. Results showed Lymphoseek and blue dye had localized most lymph nodes, although a notable number of nodes were localized only by Lymphoseek, according to the FDA.