The Food and Drug Administration said Friday that it approved a new drug from Boehringer Ingelheim for patients with a genetic variant of advanced lung cancer.

The agency said it approved the company’s Gilotrif for lung cancer patients who test positive for certain gene mutations in their tumors. The agency approved the drug alongside a diagnostic test from Qiagen NV designed to detect the mutation.

The test detects epidermal growth factor receptor abnormalities found in roughly 10 percent of patients with the most prevalent form of lung cancer, known as non-small cell lung cancer.

Patients taking the drug in company studies experienced 4 more months without their cancer spreading than patients taking chemotherapy alone. The drug did not extend survival overall.

Lung cancer is the deadliest form of cancer among men and women in the U.S. and is expected to kill nearly 160,000 people this year, according to the National Cancer Institute.

The FDA specifically approved the drug for untreated cancer that has spread from the lungs.

Common side effects of the drug include diarrhea, skin breakouts, dry skin and mouth inflammation.

“The approval of companion diagnostic tests and drugs are important developments in oncology, as they help us bring safe and effective treatments to patients who need them,” said Alberto Gutierrez, FDA’s director of in vitro diagnostics.

Shares of Netherlands-based Qiagen NV rose 60 cents, or 3 percent, to $20.52 in late New York trading. Boehringer Ingelheim is based in Germany.