WASHINGTON, May 4 (Xinhua) -- The U.S. Food and Drug Administration (FDA) approved on Friday new uses for two drugs administered together for the treatment of a kind of anaplastic thyroid cancer (ATC).

Tafinlar (dabrafenib) and Mekinist (trametinib) in combination have been greenlighted to treat ATC that cannot be removed by surgery or has spread to other parts of the body and has a type of abnormal gene called BRAF V600E.

"This is the first FDA-approved treatment for patients with this aggressive form of thyroid cancer, and the third cancer with this specific gene mutation that this drug combination has been approved to treat," said Richard Pazdur, director of the FDA's Oncology Center of Excellence.

"This approval demonstrates that targeting the same molecular pathway in diverse diseases is an effective way to expedite the development of treatments that may help more patients."

Both drugs have been approved for use, alone or in combination, to treat BRAF V600 mutation-positive metastatic melanoma.

Also, Tafinlar and Mekinist are approved for use, in combination, to treat BRAF V600E mutation-positive, metastatic non-small cell lung cancer.

Thyroid cancer is a disease in which cancer cells form in the tissues of the thyroid gland.

Anaplastic thyroid cancer is a rare, aggressive type of thyroid cancer, accounting for about 1 to two percent of all thyroid cancers.

The trial measured the percent of patients with a complete or partial reduction in tumor size, according to FDA.

Of 23 evaluable patients, 57 percent experienced a partial response and four percent experienced a complete response.

In nine (64 percent) of the 14 patients with responses, there were no significant tumor growths for six months or longer.

Both Tafinlar and Mekinist can cause harm to a developing fetus, so women should be advised of the potential risk to the fetus and to use effective contraception, FDA warned.