British pharmaceutical company GlaxoSmithKline said its Tafinlar cancer treatment had been given FDA breakthrough therapy designation for lung cancer, meaning the drug will be fast-tracked within the U.S. regulatory system.

GSK said that Tafinlar, also known as dabrafenib, was designated an FDA breakthrough therapy on Monday following interim results from an ongoing Phase II study.

Tafinlar is already approved for melanoma, the deadliest form of skin cancer.